Exercise and Sport Sciences

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Open Access
'n Ondersoek na die behoefte en deelname aan sport en fisieke rekreasie van technikonstudente met spesiale verwysing na die Orange-Vrystaat
(University of the Free State, 1987-06) Venter, Everhardus Johannes; Cruywagen, F. M.
Afrikaans: Hierdie verhandeling het eerstens ten doelom die toeretiese grondslae met betrekking tot bewegingskundige studies van vryetyd en vryetydsbesteding na te gaan ten einde 'n teoretiese verwysingsraamwerk vir die empiriese gedeelte van die studie te bepaal. Die klem val hier op die tyd en ruimtelike aspek van menslike beweging, waar tyd in besonder na vryetyd verwys, ruimte na die natuurlike- en geskepte omgewing wat die mens aanwend vir die benutting van sy vryetyd * en beweging na daardie aktiwiteite wat in hoofsaak tydens vrye tyd * beoefen word. In plaas van 'n holistiese, segmentalistiese of pluralistiese benadering volg die navorser 'n fenomenologiese benadering vir die beskrywing van vryetyd. In navolging van die beskrywende paradigma van Immorlica val die fokus in die studie op dieveelheid van dimensies van vryetyd. Vryetyd is ingevolge hierdie benadering in verskeie dimensies verdeel. Vir die dimensionele kategorisering van vryetyd is slegs die sentrale idee gebruik wat in die verskillende definisies oor vryetyd vervat is. Hiervolgens is vryetyd verdeel in universele, unieke, supraorganiese, organiese, dinamiese en statiese dimensies, as synde algemene dimensies en kwantitatiewe, ruimtelike, kwalitatiewe, funksionele, kognitiewe, konfigurale, idiële, reële en gekonstrueerde dimensies, as synde besondere dimensies daarvan. Wat die verhouding tussen vryetyd, rekreasie, spel en sport betref, is in teenstelling met die integrasionistiese, segmentalistiese en molekulêre benadering, 'n kwalitatiewe benadering in die studie gevolg. Rekreasie, spel en sport is as die konkrete onderbou van die kwalitatiewe dimensie van vryetyd beskou. Binne die bestek van die kwalitatiewe benadering is die empiriese, normatiewe en psigologiese paradigmas met betrekking tot vryetyd, spel, rekreasie en sport geakkomodeer. Die belangrikheid van vryetyd en die sinvolle benutting daarvan is by wyse van 'n omvangryke literatuurstudie ondersoek. 'n Omvattende studie is gemaak van spel, rekreasie en sport as synde die kwalitatiewe onderbou van vryetyd. Uit die literatuur blyk dit dat spel oor 'n intrinsieke beloning beskik en derhalwe hoofsaaklik proses-georiënteerd is. Rekreasie is dus weer 'n emosionele ervaring en aktiwiteit en is dus proses- sowel as produkgeoriënteerd. Beide verteenwoordig positiewe komponente van vryetyd. Sport daarenteen is in hoofsaak produk-georiënteerd. Vryetyd is 'n belangrike komponent van die daaglikse lewe van die student. Die student is inderwaarheid nie alleen "homo faber" - mens die werker nie, maar ook "homo ludens" - mens die speler. Voortreflike en produktiewe akademiese arbeid is daarom net so noodsaaklik vir die student as positiewe produktiewe vryetyd en dit setel in 'n besonder rekreatiewe sportervaring. Daarom moet spel steeds die grondslag van die rekreasie- en sporthandeling bly. Daarsonder word beide aktiwiteite gestroop van hul kwalitatiewe inhoud, word die kwalitatiewe waarde daarvan gereduseer tot die momentele en is dit nie meer 'n ryke lewenservaring nie. Wat die praktiese ondersoek betref, is 'n opname gemaak van die behoeftes- en deelnamepatrone ten opsigte van sport en fisieke rekreasie van die studentekorps aan die Technikon O.V.S. In die verband is ondersoek, ingestel na die invloed van veranderlikes soos geslag, ouderdom, kursus en woonplek op die sport- en fisieke rekreasie behoeftes- en deelnamepatrone. Die ondersoek toon dat die genoemde veranderlikes 'n beduidende invloed op die deelnamepatroon van die technikonstudent wat sport en rekreasie betref uitoefen. Oor die algemeen dui die studentegemeenskap se aktiewe deelname aan sport en rekreasie op 'n gunstige syfer van bykans 70%. Wat die 30% fisiek onaktiewe studente betref, behoort stappe geneem te word om die groep tot deelname, veral wat fisieke rekreasie betref, aan te moedig. Die oorgrote meerderheid van die damestudente is sterk ten gunste van massadeelname, terwyl die manstudente voorkeur gee aan daardie aktiwiteite met 'n oorheersende kompetisie-element. Aangesien die studentegemeenskap se voorkeure met betrekking tot sport en rekreasie na hul toetrede tot die technikon wegbeweeg van die tradisionele sportsoorte wat op skoolvlak beoefen is, kan die geleentheid benut word om veral die manstudente aan te spoor om in 'n groter mate aktiwiteite te beoefen waar die intrinsieke beloning sterker figureer.
Open Access
Factors associated with injuries sustained by players during a Currie Cup rugby competition
(University of the Free State, 2004-10) Le Roux, Douglas Leonard; Holtzhausen, L. J.; Coetzee, F. F.
English: The aim of this study was to review the available literature on the epidemiology of injuries in professional rugby, and then to collect data on previous injuries and the influence of external factors on rugby injuries. Secondly, the incidence, nature and circumstances surrounding injuries in a cohort of professional South African provincial rugby players were documented. The data collected was compared with available data in order to determine trends of injuries that, if taken into consideration, could possibly lead to the prevention of injuries to future rugby players. No study has been done on injury rate and frequency in the Currie Cup competition. Being the cornerstone of providing players for competitions like the Super 12 and Tri-nations, it is certainly appropriate to record the incidence and nature of injuries in the Currie Cup competition. This study attempted to identify factors associated with injury, to direct further analytical research and suggest measures to reduce injury rate. It also drew a comparison between results obtained through this study, and results obtained by other relevant studies in other competitions. The epidemiological data used in this study were collected from two professional rugby teams that competed in the 2002 Currie Cup Rugby Competition. This competition is held annually in South Africa and includes provincial teams from 14 regions in South Africa.
Open Access
The motor proficiency of obese 8-11 year old children
(University of the Free State, 2005) Potgieter, Carolina Frederika; Botes, S. L.; Coetzee, F. F.
English: A rapid increase in the prevalence of obesity in children has been seen around the world. There was a 60% increase in the prevalence of being overweight and a 70% increase in the prevalence of obesity between 1989 and 1998 (Ogden et al., 1997:1, Reilly et al., 1999:1039, Martorell et al., 2000:959). What’s more, motor abilities can be influenced by excess weight from a very early age. Groups of normal weight and obese babies were compared, and a delayed gross motor development was found in the obese. A significant correlation was found between excessive weight and gross motor delay. Over the following year, both weight and motor development reverted to normal in the majority of infants (Jaffe & Kosakov, 1982:619). Parizkova (1996) found that the potential deteriorating effect of excess fat on dynamic performance increases with age and the longer the duration of obesity. This researcher discovered that in preschool children, the effect of increased weight and body mass index is only apparent in some areas, such as broad jump and the 20 meter dash, and much less so in other measured variables. The significant effect of increased weight and fat is most marked during puberty. From the above mentioned statistics and research, the question is raised on whether obesity has an influence on the motor proficiency of 8-11 year old children. The first goal of the study was to identify 30 children with obesity (age 8-11) and 30 non-obese children (age 8-11) to form the control group. Body mass index was used as criterium to determine obesity. Boys with a body mass index of 18- 21kg/m2 and girls with a body mass index of 18-22 kg/m2 were identified as obese, while the control group all had a body mass index of less than 18kg/m2. Fat percentage was determined using the Heath and Carter method (skinfolds of the triceps, sub-scapula, para-umbilicus, supra-iliac, medial thigh and medial calf) (Heath and Carter, 1969:57). Furthermore, somatotyping has been used for the estimation of body composition. Somatotyping of an individual is expressed by a three digit evaluation comprising three consecutive numbers (rated from lowest to highest, 1-7) and always listed in the same order. Each number represents the evaluation of a basic component, endomorphy (relating to relative adipose), mesomorphy (relating to skeletal muscle development), and ectomorphy (relating to the relative linearity of the body). There after, the obese (n=30) and non-obese (n=30) children, age 8-11, were evaluated with the Bruininks-Oseretsky test (Bruininks, 1978) to determine their motor proficiency. The Bruiniks-Oseretsky Test of Motor Proficiency is an individually administered test that assesses the motor functioning of children from 4½ to 14½ years of age. The complete battery – eight subtests (Running Speed and Agility, Balance, Bilateral Coordination, Strength, Upper Limb Speed, Response Speed, Visual Motor Control and Upper Limb Coordination and Dexterity) comprised of 46 separate items – provides a comprehensive index of motor proficiency as well as separate measures of both gross and fine motor skills. The Short Form – 14 items from the Complete Battery – provides a brief survey of general motor proficiency (Bruininks, 1978:11). The data was analyzed by means of the t-test. This test was used because it is the most commonly used method to evaluate the differences in means between two groups. The study revealed that there was no significant difference in any age group (8, 9, 10 or 11) between the motor proficiency of obese versus non-obese children. This is in contrast with the hypothesis that states that there will be a significant difference between the motor proficiency of obese versus non-obese children. Although the study can conclude that there was no major difference between the two groups, obesity remains a concern. The prevalence of this epidemic is rising year after year and it is therefore recommended that obesity should be prevented as far as possible and that those who suffer from obesity should be treated as soon as they are diagnosed with obesity. Treatment of obesity is most successful if realistic goals are set; a balanced diet is emphasized; a safe rate of weight loss of about 0.5 kg a week is achieved through moderate reduction of energy intake (about 20-25% decrease); increased physical activity is emphasized as much as diet; parental support is strong and behavior therapy is provided to help both child and parents achieve the diet, exercise and behavior goals (Frühbeck, 2000:328). Another concern is that the motor proficiency of children between 8 and 11 years is not what it is suppose to be. Both the obese and non-obese group had a low score of motor proficiency, which means that they were probably never exposed to appropriate motor development in their early childhood years. It is therefore recommended that more attention be given to early motor development to help children improve their motor proficiency which is essential for the performance of specialized movements in later childhood and adolescence. Motor development programs may be implemented in pre-school and primary schools as part of the curriculum.
Open Access
Parental involvement in sport: perceptions of competitive adolescent swimmers
(University of the Free State, 2006-11) Stroebel, Leoni Catherine Emilie; Bloemhoff, H. J.; Walker, S.
English: All adults involved in children’s sport affect the nature of the sporting experience, and to a large extent determine whether or not it is a positive experience for children. Of all adults involved, the parents are perhaps the most important and play the most significant role in children’s sport. The purpose of this study was to examine how a group of competitive and professionally trained adolescent swimmers perceived parental involvement and how it affected their total sport experience. Participants in the study were 93 (45 male and 48 female) competitive adolescent swimmers between the ages of 13 and 22 years, who received professional coaching for 1 to 15 years, and trained for 5 to 11 months per annum. Respondents completed the parental involvement in sport questionnaire (PISQ). The questionnaire consists of three multi-item scales. The three scales measured Directive behaviour (DB), Active involvement (AI), and Praise and understanding (PU). A single item of Pressure (P) was included as a dependent variable. The questionnaire was designed to elicit responses about the behaviour of parents with regard to their children’s swimming activities. Respondents identified the frequency with which certain behaviours were (a) exhibited by, and (b) desired of their parents. Discrepancies between exhibited and desired behaviour indicated the extent of respondents’ satisfaction with these behaviours. Single sample t-tests showed that respondents perceived insufficient levels of DB, and satisfactory levels of PU, AI and P from their mothers. The results revealed that swimmers perceived satisfactory levels of pressure from their mothers, which leads to the conclusion that they find the amount of pressure acceptable. Single sample t-tests to determine the behaviour of fathers, showed satisfactory levels of DB, which suggests that fathers exhibit an appropriate level of directing or controlling of their children’s sporting experience. This is in contrast with the excessive levels of PU, AI and P that the respondents perceive from their fathers. Respondents may feel pressured by disproportionate praise as this might be accompanied by efforts to take control to an unacceptable degree. A second questionnaire was distributed to assess participants’ enjoyment of their swimming. This questionnaire consists of three questions measuring the enjoyment of sport. The data revealed that the majority of the respondents (92%) were very satisfied with their swimming experience in general and indicated that they enjoyed it to a large extent. The data suggests that the current level of pressure the swimmers experienced did not have any affect on their level of enjoyment. The study indicates that parents who express satisfaction with children’s sport performance, who interact positively with them, and who are generally positively involved and supportive in the children’s sport experience may enhance the enjoyment they derive from their sport participation. Optimal parental involvement in sport could be achieved by having well-organised, well-run programmes, and by providing parents with an opportunity to receive some education about the sport programmes in which their children are involved. A proposed document, “Practical Guidelines for Swimmers’ Parents”, was prepared in order to provide parents with a course of action to maximise their involvement. It is recommended that the above-mentioned document be distributed to the parents of the participants in this study.
Open Access
Variables contributing to satisfaction in wildlife tourism
(University of the Free State, 2007-09) Moreri-Toteng, Amanda Bobeo; Bloemhoff, J.; Saayman, M.
The study was undertaken to identify and evaluate variables that contribute to wildlife tourist satisfaction. Clark et al. (1999) argue that the hospitality and tourism industries are still relatively under researched. Therefore, this research is particularly important because it focuses on wildlife tourist satisfaction as opposed to customer satisfaction in general. According to Teye and Leclerc (1998), satisfaction is vital for ensuring sustainability of the tourism industry. Similarly, Bramwell (1998) argues that tourist destinations should offer exceptional and satisfying products and services in order to retain and attract more tourists. The study was conducted at the Chobe National Park (CNP), Botswana’s largest and most popular national park. CNP is popular for its abundant and diverse wild species. Following the arguments on the importance of wildlife tourist satisfaction the study sought to establish how wildlife tourists’ experiences impact on their overall satisfaction. The study also assessed the extent to which Chobe National Park contributes to wildlife tourist satisfaction in relation to the identified variables. The convenience sampling method was applied and the success of the pilot study indicated the usability of the research instrument. The research utilised the SERV-PERVAL scale (Petrick 2000). The scale was developed to assess service quality and perceived value. SERV-PERVAL measures quality as a measure of the supplier’s performance. The measurement of quality is crucial because quality is argued to be the best predictor of perceived value. Data was collected by the use of a structured self-completion questionnaire. The questionnaire was divided into three sections: demographic data, the SERV-PERVAL scale to assess questions on service quality, perceived value and satisfaction. The third section was a combination of a Likert scale and open-ended questions gathering information on expectations and motivations. The descriptive method of analysis, with tables and figures, was applied. The level of significance between variables was determined through the use of the correlation analysis, and the multiple regression model was utilised to investigate the contribution of variables to wildlife tourist satisfaction. The conclusion derived from the literature reviewed is that the concept satisfaction is core in the wildlife tourism industry because it involves feelings of wildlife tourists after experiencing wildlife tourism services. The literature has positively associated and it emphasised the importance of several concepts to wildlife tourist satisfaction. These concepts are: service quality, price and value for money, tourist experience and expectations. While the results of the survey condoned the significance of service quality, price, value for money and tourist experience to wildlife tourist satisfaction, they also indicated and emphasised the importance of wildlife-related variables. These are: safety measures from attack by wild animals, availability and diversity of wild species, condition of vegetation in the wildlife area and accessibility. It is through the use of these variables that wildlife tourists evaluate their experiences and rate their satisfaction levels. Some of the results are, however, in conflict with two arguments found in the literature. Firstly the results contradicted the argument that wildlife tourists assess their satisfaction on the basis of whether or not their initial expectations were met. Some tourists indicated they had a satisfactory experience and yet they did not have prior expectations before they travelled to CNP. As a result, tourists’ expectations were found not to be one of the critical variables that contribute to wildlife tourist satisfaction. Secondly, despite the argument that one benefit of tourist satisfaction is the revisits by satisfied tourists, satisfied wildlife tourists in this study indicated they were satisfied with their experience but would not re-visit CNP, mainly because they had other commitments.
Open Access
Stretching tecniques on hamstring flexibility in female adolescents
(University of the Free State, 2010) Janse van Rensburg, Lizl; Coetzee, F. F.
This study compared the eflicacy of 4 ditlerent hamstring-stretching techniques. Flexibility can be achieved by a variety of stretching techniques, yet little research has been performed on the most effective method. The four most basic stretches includes: Static stretching where the limb is held stationary at and endpoint for a certain time period; Dynamic stretching, an active stretch where the limb is slowly moved from the neutral position to the endpoint; PNF hold-relax- and PNF contract-relax stretching which is also referred to as active stretches because of the concentric and isometric contractions throughout the stretch (Prentice) 2010: Ill). This study’s aim was to determine which type of stretching technique IS most effective in improving hamstring length. One hundred female subjects between the ages of 13 and 17 years were enrolled in the study. The 90°/90° hamstring length measure was used for all measurements to measure knee extension angle. Alii 00 subjects were included in a randomized controlled trial of 5 different groups comparing different hamstring-stretching techniques. Outcorne measure (hamstring length) was recorded on all subjects initially, at 3 weeks and at 6 weeks. After 3 weeks of stretching, there was a statistically significant improvement in hamstring length (p<0.0001) using all stretches when compared to the control group. From weeks 3 through 6, hamstring length for all groups again showed statistically significant improvement when compared to the control group. No significant difference was found comparing the intervention groups after 3 weeks or after 6 weeks of stretching. After both 3 weeks and 6 weeks of stretching the straight-leg-raise (static stretching) group had the greatest improvement in hamstring length, although the difference was not statistically significant.
Open Access
Time motion analysis of international rugby
(University of the Free State, 2010-11) Schoeman, Riaan; Coetzee, F. F.
English: This study examined the relationship between the Distance covered, High Intensity Distance covered, and the Percentage Work Rate at High Intensity and how it correlates to the score and result of each match. This paper attempted to address deficiencies in the game of rugby and provide a meaningful body of data to determine winning and losing components that jeopardize matches at senior international level. Eighteen matches (Test and Super 14) were used to gather data through the Pro zone time motion analysis program. Calculating the frequency, mean duration and total time spent in activities is fundamental in time motion analysis (McLean, 1992:285-96). The extent of these changes has, however, never been quantified. What is even more important is that their impact on playing the game has not been evaluated. Teams losing the away games, even though they won all components, can be due to home team support, playing conditions, the magnitude of the game, law variations, competition structure and the team structure played. Time motion analysis is an effective method of quantifying the demands of rugby and provides a conceptual framework for the specific physical preparation of players. The results of this study showed no significant difference (p < 0.05) between the variables (distance covered, high intensity distance covered and percentage work rate at high intensity) in the winning and losing team. The correlation between all the variables (distance covered, r = 0.67 , high intensity distance covered, r = 0.62 and percentage work rate at high intensity, r = 0.54) and winning have practical implications. The information obtained from these analyses allows coaches to structure training programmes specific to the requirements of the game, and facilitates more effective training and improved performance.
Open Access
Biomechanical analysis of foot contact in junior sprinters
(University of the Free State, 2011) Hugo, Elmie; Coetzee, F. F.; Opperman, M. C.
English: The purpose of this study was to determine the effects of different foot types (normal, flat and high arch) with regards to speed, roll-over and impact forces, thus attempting to indicate if a specific foot type is dominant amongst sprinters. The different foot types of ten junior sprint athletes and ten nonsprinters were determined by walking over a pressure platform (RSscan International’s Footscan® 7.x plate system). The effects of foot roll-over and peak pressures during sprinting were determined for left and right feet respectively. The subjects ran barefoot at their top speed (sprinted) over 20 meters, crossing a pressure platform (RSscan International’s Footscan® 7.x plate system) comprising the last two meters of the 20 meter distance. The initial contact, final contact, time to peak pressure and the duration of contact of the different sub-areas of the foot were measured. The results of the sprinters’ trials were averaged and compared to the non-sprinters’ averaged trials by performing a statistical T-test. The control group (non-sprinters) dominantly has a high arch foot type for both feet. In the sprinter group, the different foot types are all represented almost equally with regards to right feet, whereas the left feet are dominantly normal type, followed by high arch and then flat foot types. There was a significant difference (p < 0.05) during the Foot flat phase (FFP) between the sprinter group (mean left: 4.04ms, mean right: 4.34ms) and control group (mean left: 26.40ms, mean right: 24.46ms), left: p=0.007; right: p=0.022. This indicates that the FFP time is significantly faster for the sprinter group than for the control group. The control group spent a higher percentage of time on the rear foot than the sprinters did (left: p=0.0057, right: p=0.0268). The control group’s peak plantar pressures were predominantly on the sub-areas of the heel (mean:HL=Left: 327.69, right: 351.44; mean HM= Left: 434.08, right: 423.19) and M1, M2, M3, whereas the sprinters’ peak plantar pressures are predominantly on the subareas of the M1, M2, M3, mid-foot and T1, meaning that sprinters predominantly have peak pressures on forefoot contact whereas the nonsprinters predominantly have peak pressures on heel contact. The results of this study therefore indicate that in general, sprinters dominantly have a normal foot type whereas the non-sprinters have a high arch foot type, and sprinters predominantly have peak pressures on forefoot contact whereas the non-sprinters predominantly have peak pressures on heel contact during sprints.
Open Access
Die verband tussen kompeteringsangs en beseringsinsidensie onder skole-rugbyspelers
(University of the Free State, 2012-01) Pretorius, Stephanus; Holtzhausen, L. J.
Afrikaans: Die doelwitte van hierdie studie was om die aard en omvang van beserings onder skole- rugbyspelers te bepaal en die verband tussen die onderskeie beseringsprofiele en kompeteringsangs te ondersoek. Die studie het die insidensie en erns van beserings onder hoërskoolleerders ondersoek gedurende 2006 – 2008 en het gepoog om te bepaal of kompeteringsangs ‘n voorspeller van beserings onder die populasie was. ‘n Totaal van 94 deelnemers het aan die insluitingskriteria voldoen en is tot die studie toegelaat. Die deelnemers se beseringsgeskiedenis gedurende 2006 - 2008 is versamel en in drie afdelings verdeel, naamlik die aantal beseerde liggaamsdele of –streke oor drie jaar periode, die aantal beserings gedurende die 2008 seisoen en die erns van beserings gedurende die 2006 en 2007-seisoene. Die omvang van kompeteringsangs is bepaal deur middel van vraelyste. Karakter-geassosieerde kompeteringsangs (KGA) is bepaal met behulp van die SCAT-vraelys en Geleentheidsgeassosieerde kompeteringsangs (GGA) met behulp van die CSAI-2-vraelys. Die insidensie van beserings was hoog in vergelyking met internasionale data. ‘n Hoë aantal beserings van ernstige aard het voorgekom, wat meer was as in vergelykende populasies. Die beseringsinsidensie van die boonste ledemate was die hoogste en die voorkoms van potensieel-katastrofiese beserings onder hierdie groep was opvallend. ‘n Positiewe verband tussen KGA en aantal liggaamsdele beseer gedurende 2006 en 2008, sowel as die aantal beserings opgedoen gedurende 2008 is aangetoon, maar geen verband kon met erns van beserings gedurende 2006 bewys word nie. Geen verband kon bewys word tussen GGA en die beseringsprofiele nie. Die studie het hoë beseringsinsidensies bevind, met veral die boonste ledemate wat prominent was. Die erns van beserings was ook opmerklik, met ‘n hoë aantal spelers wat ernstig beseer was, asook die relatief-verhoogde insidensie van lewensbedreigende beserings (nek- en rugbeserings asook konkussie) in ‘n jong populasie. In terme van identifikasie van sielkundige voorspellers, wil dit voorkom of ‘n verhoogde KGA, gemeet deur die SCAT-skaal, verband hou met beseringsinsidensie, maar nie met erns van besering nie. Dit wil voorkom of daar nie ‘n verband tussen GGA, gemeet met CSAI-2 en die beseringsprofiele, is nie. Bepaling van risikofaktore, programme om beserings te voorkom, die korrekte hantering van lewensbedreigende beserings en ‘n nasionale bewuswordingsveldtog met sentrale databasis op skolevlak word voorgestel om beserings te beperk. Verdere navorsing word aanbeveel om KGA as voorspeller van beseringsinsidensie te valideer deur herhaalstudies en om uitsluitsel te verkry omtrent GGA as voorspeller van die aard en omvang van beserings.
Open Access
Body composition and blood measurements of elite senior South African body builders during a competitive season
(University of the Free State, 2012-01) Barnard, Riaan; Holtzhausen, L. J.
A dearth of literature exists surrounding the sport of Body Building. Anecdotally, when preparing for a competition, most elite body builders in South Africa will go through two totally different phases of training and dieting. The first phase is the bulking- or weight-gaining phase. During this phase, a structured diet with high carbohydrate component and moderate to high fat content will be followed for several months. During the weight-gaining phase, Androgenic-Anabolic Steroid (AAS) substances are used in moderately high doses compared to the pre-contest period. The second phase of training and dieting, is called the pre-contest preparation phase. This is a very intense phase of high volume training that usually starts about 16-13 weeks from the time of the competition. During this phase, extremely strict, structured diets are followed, with each meal being weighed. During the pre-contest phase, a multitude of chemical substances are used to enhance the desired physique – this strategy of using combinations of different classes of drugs, is called “stacking”. This will be the period with the highest AAS substance milligram usage per week. Very little current information on the profile of these athletes is available to the South African Medical Community, especially the Sports Medicine Community. There exists only a small body of knowledge in the literature on the dosing protocols abused by these athletes and the side effects they incur. Little is known of the usage of high dose AAS amongst the elite, competitive South African Body Building population and the possible side effects. A rare opportunity was presented to the author to study a group of elite level body builders during the 2010 competitive season. Obtaining participants for this cohort was difficult as these athletes form part of a very secluded group of sportsmen. Though the present cohort was disadvantaged in small cohort size, the opportunity to study such a group in depth will not be readily repeated. This is a novice study – to present, no similar study has been conducted in South Africa. All the athletes registered with the International Federation of Body Building South Africa were invited to participate in the study. Interested volunteers were asked to contact the researcher. More than 200 invitations were sent out to the existing database – only 19 athletes conveyed their interest in participation. Eventually, only 14 athletes partook in the full protocol. Blood assays were performed on each athlete on 3 different occasions, while anthropometric measurements and blood pressure readings were taken on 4 different occasions over the length of the competitive season. Each individual athlete recorded his AAS abuse, while some athletes provided sample diets as well. Data was captured on Excel spread sheets and forwarded to Department of Biostatistics, University of the Free State, South Africa. Along with the concomitant abuse of high doses of AAS over extended periods, the present study also found: - Minimal changes in blood pressure - Initial decrease in lean mass, followed by rapid increase in lean mass in just one week and failure to maintain that gain over the following weeks - Disturbed carbohydrate metabolism with increased risk for pre-diabetic status - Lipid profile changes, with decreased HDL, unchanged Total Cholesterol and decreased LDL - Liver enzyme changes highly suggestive of AAS-driven adverse effects - Hypogonadotrophic hypogonadism status - Very high Androgen Status for the cohort with mean total AAS abuse per week measuring 1638,3 mg, with average AAS cycle lengths of 17.43 weeks. In conclusion, it should be noted that the present study’s cohort differed vastly from cohorts from other studies in the literature, as none of the latter observed cohorts under full pre-contest preparation conditions. It should also furthermore be understood that body builders under full pre-contest preparation will respond differently to the use of special diets, different training strategies and different types of AAS abused, than compared to when they train under normal out-of season conditions. The author recommends that sports physicians should continuously target their efforts at counselling adolescents and other athletes about the potential long-term harms of AAS abuse, as well as regularly and prudently follow-up on the potential adverse effects that may develop in current AAS abusers. The author further recommends that, if an opportunity to study such a secluded group of body builders would present itself again, it should be immediately fully utilised.
Open Access
Attitudes and insights of Free State Swimming coaches towards scientific coaching principles
(University of the Free State, 2013-02) Jones, Colleen Jo-Ann; Bloemhoff, H. J.; Coetzee, F. F.
English: Objectives: The aim of this study is to determine the attitudes and insights of swimming coaches in the Free State Aquatics region towards scientific coaching principles. A comparison between performance coaches and participant coaches’ scientific coaching principles to improve performance or participation levels in swimming were recorded. Methods: This study was done by sampling data via quantitative research (i.e. a questionnaire). All swimming coaches who were at least 18 years old, regardless of their level of qualification, affiliated or not with Free State Aquatics, were invited to participate in the study. A questionnaire was compiled using data from various research sources. All coaches were categorised into a participant or performance coach. The researcher captured data from the data forms to Microsoft Excel. A statistician conducted further analysis using SAS Version 9.1.3. Frequencies and percentages were calculated for categorical data. For numerical data, where data were evenly distributed, means and standard deviations were calculated. Medians and percentiles were calculated where data were not normally distributed. The Student’s T-test was used to compare mean values between the two groups, whereas the Kruskal-Wallis test was used to compare median values. The appropriate p-values and/or confidence intervals were reported. For the dependent data, the mean or median differences were calculated within the groups. The Student’s T-test, or Wilcoxon signed rank test, was used to test for significant median differences. A Fischer Exact test was used to test for significant frequency differences. A significance level of p ≤ 0.05 was used throughout the research study. Results: Seventy one percent of the participant coaches and 29% of the performance coaches participated in the research study. Out of a total of 42 participants (coaches), 21% were male and 79% were female. An alarming result was that 36% of coaches had no qualifications in swimming coaching whatsoever, but are currently involved in coaching. Almost half (46.7%) of the participants have no swimming coaching qualification, while 41.7% of the performance coaches only have a ‘Learn to Swim’ qualification. Only 23.8% of all coaches (participant and performance coaches) are registered with SSA, which is compulsory. Therefore, 76.2% of all coaches are not compliant with SSA rules and regulations pertaining to a coach. As expected, performance coaches rated professional knowledge (50%) and interpersonal knowledge (58.4%) as very important. This differs from participant coaches who indicated that professional knowledge (50%) was important to them. Performance coaches preferred learning methods through internal learning (75%) and unmediated learning (58.4%). Participant coaches reported that internal learning (56.7%) and mediated learning (40%) were their preferred learning methods. Differences between performance and participant coaches’ characteristics are passion and enthusiasm and love for the sport, as demonstrated by performance coaches. This is contradictory to the main goal of participant coaches who would like to instil an element of fun in swimming, in order for the swimmers to gain passion and enthusiasm and ideally love for the sport so that they continue with swimming. In comparison, a participant coach’s role as a friend differed significantly from performance coaches (p = 0.0437). This coincides with their strategy of integrating professional and personal life while coaching. There was no significant difference between participant and performance coaches with regard to the multi-disciplinary involvement in performance improvement. Conclusions: It is alarming that almost half of the current swimming coaches have no qualifications at all. SSA and FSA must enforce stricter rules and regulations regarding coaching, so that all coaches have the minimum qualification in relation to their level of coaching. Various learning methods must be employed to develop numerous knowledge components to achieve optimal scientific coaching.
Open Access
Physical activity and lifestyle aspects of female students at a tertiary institution
(University of the Free State, 2013-07) Losper, T'Neil Sarelle; Opperman, M. M.; Coetzee, F. F.; Bloemhoff, H. J.
English: BACKGROUND AND RATIONALE: It is generally believed that a sharp rise in chronic diseases and unhealthy living has occurred. Researchers believe that the modern lifestyle and a lack in physical activity (PA) are the main reasons for this problem (McGinnis, 1992:S196). Chronic diseases and obesity are factors that can be prevented or reduced with physical activity and a healthy way of living. The way in which physical activity can have an indirect influence on conserving health can be explained in two ways: Firstly physical activity can be used as trigger mechanism to change other destructive lifestyle habits (Weinstein, 1987:8; Eddy & Beltz, 1989: 168). Secondly, participation in PA can have an indirect effect on the reduction of coronary diseases because of its reducing effect on depression, anxiety and tension, to name a few (Willis & Campbell, 1992:47). According to Bray and Born, (2004:181) there is an increasing need for physical activity among young adults. Young adults attending universities gain increased control over their lifestyles. However, they may not necessarily develop positive behaviors like regular PA. The lifestyle that students live is questionable. Whether their activity levels are adequate and whether they generally lead to healthy lifestyles is unknown as little research is available on this matter, especially in South Africa. Keating, Guan, Pinero and Bridges (2005:116) stated that it is well known that students' PA as a research topic has been seriously neglected. Young adulthood is considered to be an important phase of life, as many lifelong health behaviour patterns are established during this phase (Timperio, Salmon & Ball, 2004:20). OBJECTIVES: The purpose of the study is twofold: 1. To identify PA levels of undergraduate female students indifferent ethnic groups on a South African university campus, and 2. To establish the lifestyle profile and body composition of female students in different ethnic groups in a South African university campus. RESEARCH METHODS: The sample constituted of female students at the University of the Free State in their 1st, 2nd and 3rd year+ of study residing on the campus. The sample consisted of 244 students (78 1st years, 98 2nd years, 68 3rd years-: 139 black, 21 coloured and 84 white students). The following three research instruments were used: • International Physical Activity Questionnaire (IPAQ) (2012) • Belloc and Breslow's 7 lifestyle habits questionnaire • The Heath and Carter anthropometrical assessment. RESULTS AND DISCUSSION: By comparing the 1st, 2nd and 3rd year groups it is evident that 40.16% of the group as a whole (all ethnic groups) did take part in some form of physical activity. Fifty five point one percent (55.13%) of 1st year female students, 42.86% of the 2nd year and 44.12% of the 3rd year female students participated in PA. The White female students had the highest physical activity participation rate (67.86%), followed by the coloured students (38.10%). The black students' physical activity participation (35.97%) was the lowest. An average of 4 out of the 7 lifestyle habits being followed by the majority of the participants. The majority of participants eat breakfast daily (51.64%) but they do not eat 3 meals per day. Eighty seven present (87.70%) of the sample are nonsmokers, with 77.05% of the respondents consuming little to no alcohol, and at least 66.80% of the group maintains a healthy body weight. Unfortunately their eating, sleeping and exercise habits are not optimal. It is evident that the lifestyle habits of the students decrease from the 1st to the s= year, but that by the time they progress to the 3rd year-, they start trying to change their lifestyles habits to a certain extent. The ethnic groups do not show a significant difference among their lifestyle habits but white female students do have a more positive profile.
Open Access
Morphological and skill-related fitness components as possible predictors of injuries in elite female field hockey players
(University of the Free State, 2014) Naicker, Marlene; Coetzee, F. F.
Introduction: The incidence of injury in female field hockey players is high, but there is little data on the physical demands of the game or the injury risk factors. Objective: To establish an athletic profile of elite female field hockey players and to determine if morphological or skill-related factors measured in the pre-season can predict injury in the in-season. Methods: Thirty female field hockey players comprising the South African national field hockey team underwent pre-season testing. These tests included anthropometry, balance, flexibility (sit and reach test), explosive power (vertical jump test), upper and lower body strength (bench and leg press), core strength, speed (10 m, 40 m and repeated sprint test with and without a hockey stick), agility (Illinois test) and isokinetic testing of the ankle. Also included was a questionnaire to collect information on demographic data, elite-level experience, playing surface, footwear and injury history. Injuries in training and matches were recorded prospectively in the subsequent season using an injury profile sheet. Players reporting an injury were contacted to collect data regarding injury circumstances. Univariate and multivariate regression analyses were used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for ±1 standard deviation of change. Results: A total of 87 injuries were recorded with ligament and muscle injury the most frequent. The highest incidence of injury was the ankle joint followed by the hamstring muscles and lower back respectively. Univariate analyses showed that ankle dorsiflexion strength was a very strong predictor of ankle injuries (p=0.0002), and that ankle dorsiflexion deficit (p=0.0267) and eversion deficit (p=0.0035) were significantly good predictors of ankle injury. All balance indices, i.e. anterior/posterior (p=0.0465), medial/lateral (p<0.0001) and overall (p<0.0001), constituted the other pre-season performance measures showing significant potential to predict ankle injury. For lower leg injuries, univariate associations were found with ankle inversion deficit (p=0.0253), eversion deficit (p=0.0379) and anterior/posterior balance index (p=0.0441). Conclusion: Dorsiflexion strength and all balance indices were strong predictors of ankle injury while ankle inversion deficit, eversion deficit and anterior/posterior balance were associated with lower leg injuries in elite female field hockey players.
Open Access
A perceptual-motor intervention programme for grade 1-learners with developmental coordination disorder
(University of the Free State, 2015-02) De Milander, Monique; Coetzee, F. F.; Venter, A.
English: Background Developmental coordination disorder (DCD) is recognised as one of the most common developmental dysfunctions during childhood. Developmental coordination disorder is diagnosed in children who experience significant difficulties in motor learning and in the performance of functional motor tasks that are critical for success in their daily lives. However, one of the major concerns regarding children with DCD is that they are often not formally diagnosed, but rather described by their parents and teachers as lazy or awkward. In an attempt to identify children with DCD, several research tools, such as questionnaires for screening purposes and norm-referenced tests to measure the degree of movement difficulties, can be used. Even though children will not outgrow this disorder as previously believed, children can be helped by means of various interventions. Aims The first aim of this study was to determine the prevalence of DCD among Grade 1 children in Bloemfontein. The second aim was to establish the ability of parents to identify Grade 1 children with DCD at home; in addition the third aim was to establish the ability of teachers in identifying Grade 1 children with DCD in the classroom. The fourth aim was to explore the influence of DCD on learning related skills. Aim five and six was to determine if the application of a perceptual-motor intervention as well as a sport stacking intervention will significantly improve the motor proficiency status of Grade 1 children identified with DCD independently. Method Participants For the purpose of aim 1, 559 participants’ between the ages of 5 and 8 years took part in this study. There were n=321 girls and n=238 boys. Aim 2 include 410 participants and consisted of n=226 girls and n=184 boys, whilst aim 3 had 506 participants and there were n=289 girls and n=217 boys. Furthermore, aim 4 had 347 participants including n=190 girls and n=157 boys. Aim 5 and 6, which relates to the two interventions used in this study was as follows. Seventy six (76) participants took part in the perceptual-motor intervention. The group consisted of girls (n=34) and boys (n=42) classified with DCD. The intervention had a pre-test/post-test experimental design (n=36) with a control group (n=40). With reference to the sport stacking intervention, 18 children between the ages of 6 and 7 years took part in this study. The group consisted of girls (n=6) and boys (n=12) classified with DCD. This intervention also had a pre-test/post-test experimental design (n=10) with a control group (n=8). Measuring instruments The instrument used to assess the participants motor proficiency levels and to identify symptoms of DCD was the Movement Assessment Battery for Children-2 (MABC-2 Test). This test includes manual dexterity, balance as well as aiming and catching, in addition the three sub-tests constitute a total test score. In order to determine if parents possess the ability to identify symptoms of DCD at home the Developmental Coordination Disorder Questionnaire ’07 (DCDQ’07) was used. With the purpose of determining if teachers possess the ability to identify DCD in the classroom the Movement Assessment Battery for Children-2 Checklist (MABC-C) was used. It is designed to identify primary school children likely to have movement difficulties. The Aptitude Test for School Beginners (ASB) was administered by qualified teachers to all participating children in the first two months of the school year. A requirement of the ASB is that it must be presented and completed in a child’s mother tongue. The ASB is a norm-based instrument and consists of eight sub-items, which include perception, spatial skills, reasoning, numerical skills, gestalt, coordination, memory and verbal comprehension. Each sub-item is evaluated by means of a standard score out of five. An evaluation score of 1 is regarded as below average and an evaluation score of 5 as above average. The aim of the ASB is to obtain a differentiated picture of certain aptitudes of grade 1 children. Data analysis Analysis of the data was done by a biostatistician using Statistical Analysis Software Version 9.1.3. Descriptive statistics, namely frequencies and percentages, were calculated for categorical data. Medians and percentiles were calculated for numerical data. Median differences were tested by calculating p-values using the signed-rank test. The Chi-square statistics were used to test for proportion differences. This was used to determine the prevalence of DCD (article 1), as well as for learning related skills and DCD (article 4) and for the sport stacking intervention (article 6). Furthermore, data analysis was performed using the Statistical Package for the Social Sciences (SPSS) for Windows (SPSS version 16.0), in order to determine if parents and teachers possess the ability to identify children with DCD. The convergent validity of the classification of motor problems (no motor difficulties or motor difficulties) using the MABC-2 Test and the classification of motor difficulties (no motor difficulties or motor difficulties) by the parents of the participants using the DCDQ’07 and the teachers using the MABC-C, the kappa (k-) coefficient was used. Finally, the Mann-Whitney-U test was used to compare differences between the experimental- and control group with reference to the perceptual-motor intervention for children with DCD (article 5). Probability level of 0.05 or less was taken to indicate statistical significance. Results The results of aim 1 revealed the prevalence of DCD amongst Grade 1 learners in Bloemfontein is estimated to be 15%. The results also indicate that boys have a significantly higher (p=0.050) prevalence of DCD although marginally when compared to their female counterparts. Aim 2 indicated a 15% convergent validity between the MABC-2 Test and the DCDQ’07, similar results were obtained for aim 3, indicating a 11% convergent validity between the MABC-2 Test and the MABC-C. Therefore, it can be argued that parents using the DCDQ’07 and teachers using the MABC-2 could not identify children with DCD at home or in the classroom. The results in aim 4 indicated the prevalence of DCD to be 12%. Additionally, DCD had a significant effect (p=0.050) on five of the eight learning-related subtypes, namely reasoning, numerical skills, gestalt, coordination and memory. Furthermore, the results of aim 5 indicated that a perceptual-motor intervention only improved balance as a sub-test of the MABC-2 Test. Interesting to note is that children taking part in Physical Education classes presented by the teachers also prove to be beneficial. In contrast, aim 6 (sport stacking intervention for DCD) showed that the intervention had a significant effect (p=0.050) on two of the three sub-tests, namely manual dexterity, balance, as well as the total test score. This suggests that sport stacking can be used as an effective intervention programme for children with DCD. Conclusions The results revealed that the school age children in the current study had a higher incidence of DCD (15%) compared to the findings reported in the literature (5-6%). This information is important, and indicates that appropriate screening tools should be used to identify children earlier. Unfortunately the reliability of the MABC-C and the DCDQ’07 completed by parents and teachers to identify children with DCD was found to be low. Therefore it is recommended that specific norms should be developed for South African children. Furthermore, the results revealed that children with DCD do struggle with learning related skills. This knowledge enables teachers to address the specific needs of children with DCD. It can be concluded that perceptual-motor interventions have more often than not positive effects on children with DCD; however it is recommended that a combination of the bottom-up approach and top-down approach should be used for optimal results.
Open Access
The development of a measuring instrument to determine the knowledge and attitudes of elite adolescent athletes about ergogenic aids and banned substances
(University of the Free State, 2016-02-09) Welthagen, Amanda; Holtzhausen, L.; Van der Merwe, P.
The use of sports supplements and banned substances amongst adolescent athletes is high. The literature review reveals that supplement and banned substance use is a complex health and social issue. Athletes use supplements in the belief that it improves performance in various ways, although there is a lack of scientific evidence of the efficacy and safety of nutritional supplements. Health risks exist with regard to using supplements due to lack of quality control and contamination with banned or dangerous substances. Contamination can cause inadvertent doping offences. A continuum from supplement use to banned substance and recreational drug use was identified. The use of banned substances have pronounced health, psychological and socio-ethical risks. The risk of getting ostracised for a doping offence is probably limited to elite sports. Banned substance use is driven by the belief that others are using it and not following suit reduces the chances of athletic success. Especially adolescents are vulnerable to controlling influences from significant others. Athletes with an external locus of control are more prone to use supplements and banned substances. Moral disengagement has been associated with the use of banned substances. The zero tolerance (ZT) approach to doping by the World Anti-Doping Agency (WADA) has not reduced the prevalence of doping. The harm reduction (HR) approach accepts the reality of widespread doping in sports and approaches the problem with the social drivers of doping in mind. Many athletes are willing to use substances to achieve their goals even at the expense of their health and wellbeing. It is therefore important to not only evaluate the prevalence of use in the adolescent athlete population, but to develop effective preventative interventions. Understanding adolescents’ knowledge, their preferred sources of information, attitudes and beliefs about sports supplements and banned substances are required in this regard. Therefore, the aim of this study was to develop a reliable measuring instrument (questionnaire) to be used in South Africa to assess the knowledge and attitudes of adolescent athletes about ergogenic aids and banned substances. The study was done in two phases. A mixed method research model was used to gather both quantitative and qualitative data. In the first phase of the study a questionnaire was developed and the relevancy and validity of the questionnaire ensured by means of qualitative research methods. In the second phase, the questionnaire was tested with a cohort of elite adolescent athletes of the University of the Free State Athletics Club, where both quantitative data (closed-ended questions) and qualitative data (open-ended questions) about the habits and knowledge of the cohort were gathered and analysed. The questionnaire was assessed as functional and user friendly. The majority of the athletes in the test population (90%) reported the use of sports supplements in the previous six months; however, all the participants (100%) claimed that they would refuse the use of banned substances even if its use was encouraged by a coach or trainer. The main reasons for using sports supplements were reported as “to increase energy” (65%), “aiding recovery” (45%), “to improve endurance” (35%), “to improve strength” (20%) and “to improve sporting performance” (15%). Thirty-five percent (35%) of the participants indicated that they were not aware of any dangers of sports supplements. Supplement information was obtained from the internet (35%), coaches (30%) and friends (30%). This complex social and health issue requires in-depth analysis and intervention, including holistic educational programmes. If these factors are addressed and their effects monitored, a positive contribution could be made to the knowledge and attitudes of adolescent athletes about ergogenic aids and banned substances in South Africa.
Open Access
Positional match statistics in Currie Cup and Super Rugby competitions between winning and losing teams
(University of the Free State, 2016-11) Schoeman, Riaan; Coetzee, F. F.
English: Background Rugby union (here after referred to as rugby), as most other team sports, is becoming more aware of statistics as a reliable method to evaluate players and match variables during match play. This non-invasive evaluation method provides coaches and conditioning coaching with much needed information regarding player attendance to match situations and the successful execution of these match situations. Winning and losing teams from all levels of competitions use statistics to not only evaluate the team’s performance, but to determine which variables might be responsible for the outcome of the game. It is accepted that teams from a winning side might perform better in certain areas of play than losing teams, and players from higher levels of participation can execute certain skills more effectively. Previous research has been conducted on various teams from different participation levels on the physiological differences, mental toughness and match variables. The increased professionalism of rugby players may also indicate an increased ability of players from one season to the next. The ability of players will also vary from one position to the next and may be approximately exposed to certain match variables. Aims The first aim of this study was to determine the tackle and collision count for Super Rugby players during the 2013 competition. The second was to analyse the passing and kicking statistics that discriminate between winning and losing teams during the 2014 Super Rugby season. Thirdly, the study attempted to differentiate between the Super Rugby competition and the Currie Cup competition according to the occurrence of match activities and lastly to evaluate the evolution of the Super Rugby competition from 2011 to 2015 by the use of regression statistics. Method Sample The first aim consisted of conducting an analysis of 1,900 players from 30 games played during the 2013 Super Rugby competition. Two games from each of the participating franchises were used and selected in regards to number of matches available and balance of the sample. The second aim included an analysis of 1298 players from the 2013 Super Rugby season, whilst the third aim involved 1800 players with n=900 players from Super Rugby and n=900 players from the Currie Cup competition. Furthermore, aim 4 consisted of 4500 players and included n=900 from each of the Super Rugby seasons from 2011 to 2015. Measuring instruments Data was supplied by the Cheetahs Super Rugby Franchise, Bloemfontein, South Africa, using the Verusco TryMaker Pro. Verusco has provided Super Rugby teams with TryMaker Pro since the year 2000. TryMaker Pro is the most advanced analysis system custom-made for rugby, and it is the preferred system for the professional teams using Verusco. The Verusco coding centre codes all the games for registered teams and delivers high-detail, high-speed analysis within hours of the game having been played. Data analysis All data were captured in Microsoft Excel 2007 and subsequently converted into an SAS data set. For aim 1 the following analysis was done: The GLIMMIX procedure of the SAS Version 9.22 statistical software package was used for further statistical analysis (SAS, 2009). Means and standard deviations were used for numerical data. Individual tackle counts for each position, team and game were analysed using a generalised linear mixed model (GLIMM) with position and team as fixed effects, the natural logarithm of individual time played in minutes as offset, and position-by-team and game-by-team interaction terms as random effects. Regarding the fitted random effects, it seemed reasonable to allow for correlation between tackle counts for a specific individual across several games (modelled by the position-by-team random effect), and for correlation between tackle counts across players in a given team and game (modelled by the team-by-game random effect). Furthermore, the GLIMM was specified with Poisson error distribution and the natural logarithm as link function. Individual collision counts for each position, team and game were analysed in the same manner. In both cases – tackle counts and collision counts – the model fitted the data well and there was no evidence of residual over-dispersion. Based on the GLIMM, the mean rate of tackles and mean rate of collisions per 80 minutes (that is, normalised to a full-length rugby game) were estimated for each playing position, with 95% confidence intervals (CIs) of the mean rates. Similarly, in order to compare the mean rates of tackles and collisions between different playing positions, rate ratios (that is, the ratio of tackle and collision rates between playing positions) were estimated, with 95% CIs for the rate ratios. Aim 2 included the following statistical analysis: Means and standard deviations were used for numerical data. Individual tackle counts for each position, team and game were analysed using a generalised linear mixed model (GLIMM) with position and team as fixed effects, the natural logarithm of individual time played in minutes as offset, and position-by-team and game-by-team interaction terms as random effects. Regarding the fitted random effects, it seemed reasonable to allow for correlation between tackle counts for a specific individual across several games (modelled by the position-by-team random effect), and for correlation between tackle counts across players in a specific team and game (modelled by the team-by-game random effect). Furthermore, the GLIMM was specified with Poisson error distribution and the natural logarithm as link function. Team rates for passing and kicking were analysed in the same manner. In both cases, passing and kicking rates, the model fitted the data well and there was no evidence of residual over-dispersion. Based the GLIMM, the mean rate of passing and mean rate of kicking per 80 min were estimated for each team, with 95% confidence intervals (CIs) of the mean rates. Aim 3 consisted of each count variable (number of lineouts, scrums, rucks, mauls etc.) to be analysed using a generalised linear mixed model (GLIMM) with season (2011 versus 2015) as fixed effect, and both winning team and losing team as random effect. (The fitting of the variables winning team and losing team as random effects allowed for correlation between the counts in question for a given team across several games.) Furthermore, the GLIMM was specified with Poisson error distribution and the natural logarithm as link function; residual over-dispersion was allowed for in the model. Based on the GLIMM, the mean rates of lineouts, scrums, rucks, mauls etc. per game were estimated for the 2011 and 2015 seasons. Similarly, in order to compare the mean rates between the 2011 and 2015 seasons, ratios of lineout rates etc. between the 2015 and 2011 seasons were estimated, together with 95% CIs for the rate ratios. The above analyses were carried out separately for the data of the winning teams, for the data of the losing teams, and for the data of two teams involved in each game combined (that is, for the game). The analysis was carried out using SAS procedure GLIMMIX (SAS, 2013). Aim 4 used descriptive statistics for the count and percentage data calculated for the 2011 to 2015 seasons. Descriptive statistics were calculated per season for the winning teams, for the losing teams, and for the two teams involved in each game combined (that is, for the total count per game). Each count variable (number of lineouts, scrums, rucks, mauls etc.) was analysed using a generalised linear mixed model (GLIMM) with Season (2011 versus 2015) as fixed effect, and both winning team and losing team as random effect. (The fitting of the variables winning team and losing team as random effects allowed for correlation between the counts in question for a given team across several games.) Furthermore, the GLIMM was specified with Poisson error distribution and the natural logarithm as link function; residual over-dispersion was allowed for in the model. Based on the GLIMM, the mean rates of lineouts, scrums, rucks, mauls etc. per game were estimated for the 2011 and 2015 seasons. Similarly, in order to compare the mean rates between the 2011 and 2015 seasons, rate ratios, that is, ratios of lineout rates etc. between the 2015 and 2011 seasons were estimated, together with 95% CIs for the rate ratios. The above analyses were carried out separately for the data of the winning teams, for the data of the losing teams, and for the data of two teams involved in each game combined (that is, for the game). Percentage territory and percentage possession of the winning team in each game were analysed using a linear mixed model with Season as fixed effect, and both Winning Team and Losing Team as random effects. Based on the linear mixed model, the mean percentage territory (and possession) was estimated for each season, together with a 95% CI for the mean percentage. Similarly, in order to compare the mean percentage between the 2011 and 2015 seasons, mean differences, that is, differences of mean percentage territory and possession between the 2015 and 2011 seasons were estimated, together with 95% CIs for the mean differences. The analysis was carried out using SAS procedure MIXED (see SAS, 2013). Results The results from aim one underlined the importance of specific demands on the various playing positions regarding the tackles and collisions sustained by Super Rugby players. Clearly, loose forwards (6: = 16.65 tackles/80 min; 7: = 17.30 tackles/80 min; 8: = 14.68 tackles/80 min) had the highest tackling rates, followed by the locks (4: = 13.74 tackles/80 min; 5: = 14.07 tackles/80 min). Amongst the backs, the inside centre (12: = 12.89 tackles/80 min) was the player with the highest tackling rates, followed by the outside centre (13: = 9.96 tackles/80 min). The results showed that the open-side flanker (7) had the highest tackle rate of all playing positions (17.30 tackles/80 min). The open-side flank (7) was involved in the most collisions (50.91), followed by the blind-side flank (6), loosehead lock (4) and eighthman (8), with collision rates of 46.08, 44.81 and 43.03 respectively, per 80 minutes collision count per game. The results showed significant differences between positional groups for tackles, except for the front row players and the second row (1, 2, 3 vs 4, 5; p=0.0715 to p=0.6324). Within a positional group, namely the backline players, the tackling rate of the inside centre differed significantly from the tackling rate of the other backline players (9 vs 12, p=0.0029; 10 vs 12, p=0.0045; and 12 vs 13, p=0.0100). Aim two indicated that losing teams tend to pass the ball more (157.41) than winning teams (127.02). The results illustrated a significant difference between winning teams and losing teams regarding total passes, bad passes, and good passes (p=<0.05). Winning teams tend to kick the ball more (25.77) than losing teams (20.23). Results indicated a significant difference between winning teams and losing teams regarding total kicks, long kicks, short kicks, and kicking metres (p=<0.05). Winning teams kicked more long kicks (18.55) than losing teams (14.19). Winning teams also used the short kick (7.22) more effectively and more often than losing teams (6.04). Losing teams gain a mean total of 660.01m per game in comparison to winning teams who gain 901.4m per game. In the third aim it was discovered that, when the two competitions are compared, it is evident that only two variables can be distinguished. The mauls and tackles missed are the only two variables that show remarkable difference, with 3.23 mauls and 8.9 tackles missed per game more in Currie Cup competition than the Super Rugby. The results of this study underline the importance of measuring and analysing specific performance indicators on a regular basis as these performance indicators can increase or decrease as the level of competition change. The greatest increase occurred with rucking, as this variable increased from 139.63 in Currie Cup to 143.13 in Super Rugby. Super Rugby teams lose fewer lineouts, and have less missed tackles, while Currie Cup teams utilise mauls more as an offensive weapon. Aim 4 identified playing time, lineouts lost, scrums, scrums lost, tackles and penalties decreased from 2011 to 2015, while lineouts, mauls and the number of missed tackles increased. The results of this study underline the importance of measuring and analysing specific performance indicators on a regular basis as these performance indicators can increase or decrease in a short time frame. From 2011 to 2015 winning teams consistently lost fewer lineouts than losing teams, even with an overall increase in the number of lineouts per game. The study indicates a slight decrease in the number of tackles, but still supports the fact that winning teams have higher tackle rates than losing teams. Conclusions The results of the study show that there are significant differences between individual playing positions within the same positional group with regard to tackling and collision rates sustained during match play. The study confirms that losing teams pass more than winning teams and that winning teams kick more than losing teams during match play. The study also discovered a greater distance gained through kicks by winning teams. The higher or lower numbers of performance indicators performed by teams over competitions emphasise the different physiological demands for teams. The study concluded that playing time, lineouts lost, scrums, scrums lost, tackles and penalties decreased from 2011 to 2015, while lineouts, mauls and the number of missed tackles increased. The findings may be important for future research as they indicate a constant shift in statistics and outcomes of teams over seasons within a particular competition.
Open Access
Time motion analysis of elite under 19 female netball players using GPS technology
(University of the Free State, 2018-01) Shaw, Michael-Louis; Coetzee, F. F.; Kraak, W. J.
Introduction: Netball is a high intensity team sport characterized by short bursts of movements coupled with less intense recovery periods. Understanding the physiological demands of the sport is essential for constructing sport-specific conditioning programmes. Objectives: The purpose of this study was to profile the physical characteristics and physiological demands on elite u/19 female netball players during netball matches, in an attempt to assess the differences in those characteristics and demands for the various playing positions in netball. Methods: Global Positioning System (GPS) data on a total of forty-four (44) elite junior netball players (u/19A) were collected and a total of sixteen netball matches were analysed for the study. Therefore, a total of hundred and forty (140) GPS data sets (player games) were analysed (equivalent to 560 (140 x 4) player quarters out of a total of 731 player quarters that were recorded). Minimax X4 Catapult GPS units as well as a Polar HR monitors and chest straps were used to determine the physiological demands of netball players. The following variables were recorded: Distances covered, player load, the maximal velocity during the match; and heart rate (HR) response. The various HR and GPS data variables were analysed using a linear mixed model with Playing Position as fixed effect, and the random effects Game, Team, Game x, Team interaction term, and Player. Fitting these random effects allowed for correlation between the observations in question due to multiple observations from the same game, team, and player. Based on this linear mixed model, the mean values of the variable for each playing position were estimated, together with their standard errors. Furthermore, the pairwise mean differences between playing positions were estimated, together with 95% confidence intervals (CIs) for the mean differences and P-values associated with the null-hypothesis of zero mean difference between the pair of playing positions in question. Results: The body weight, body fat percentage and height of u/19 female netball players vary according to playing position. The Goal Shooter (GS) (186 b/min) recorded significantly (p<0.05) lower mean maximum HR than all the other positions. The mean HR of the GS (162 b/min) and the Goal Defence (GD) (170 b/min) was significantly lower than the Centre (C),Goal Attack (GA) (180 b/min) and WA (178 b/min). The C presented with the highest mean maximum velocity (5.23m.s-1) whereas the GS recorded the lowest mean maximal velocity of 4.05m.s-1. The C also covered significantly (p<0.05) more distance and presented with significantly (p<0.05) higher Player load (PL) than all the other positions, whereas the GS and the Goal Keeper (GK) presented with significantly (p<0.05) lower distance covered and PL. However, the GS and GK had a significantly higher PL per meter. The C covered 44% of its total distance between 0.2 – 3.6 m.s-1 whereas the GK and GS covered 77% of their total distance between 0.2 – 3.6 m.s-1. The GS and GK covered significantly (p<0.005) more distance in velocity band 1 than the C, GA, GD and Wing Attack (WA) and the Wing Defence (WD) travelled significantly (p=0.007) further than the C in velocity band 1. However, the GK and GS covered significantly (p<0.05) less distance than all the other positions in velocity band 2. The C travelled significantly (p<0.05) further than all the other positions in velocity band 3 and 4 and the GK travelled significantly (p<0.05) less in velocity band 4 than the other positions. Conclusions: The study revealed the differences in physical profile and physical demands of u/19 female netball players between the seven playing positions. These findings emphasize the difference in physical demand between the different positions as well as the different type of load placed on the different positions. Coaches and conditioning coaches must implement the findings of the study to develop sport-specific, and more importantly, position-specific conditioning programs.
Open Access
Time motion analysis of varsity cup soccer
(University of the Free State, 2018-12) Masingi, Sam; Schoeman, Riaan
Introduction: Soccer is an intermittent sport characterised by periods of moderate-intensity running and short high-intensity bursts. Understanding the physical and physiological demands of the sport is essential for constructing sport-specific and position-specific conditioning programmes. Objectives: The purpose of this study was to quantify the physical and physiological demands of different positions in second division soccer. The main focuses calculated were the total distance covered, distance covered in high-intensity, distance covered in different velocity categories, and player load of the different positions in second division soccer and to compare results to higher level leagues. Methods: GPS data on a total of twenty-four (24) players were collected and a total of thirteen soccer matches were analysed for the study. Therefore, a total of hundred and forty-nine (149) GPS data sets (player games) were analysed. Minimax X4 Catapult GPS units, as well as a Polar HR monitors and chest straps, were used to determine the physical and physiological demands of soccer players. The following variables were recorded: Distances covered, player load, the velocity bands during the match; and heart rate (HR) response. The various HR and GPS data variables were analysed using a linear mixed model with Playing Position as fixed effect, and the random effects Game, Team, Game x, Team interaction term, and Player. Fitting these random effects allowed for correlation between the observations in question due to multiple observations from the same game, team, and player. Based on this linear mixed model, the mean values of the variable for each playing position were estimated, together with their standard errors. Furthermore, the pairwise mean differences between playing positions were estimated, together with 95% confidence intervals (CIs) for the mean differences and P-values (p<0.05) associated with the null-hypothesis of zero mean difference between the pair of playing positions in question. Results: Soccer players in the current study performed at 75% of the maximum HR. The CM had the highest mean HR (161.5 b/min), while the GK had the lowest mean HR (143.3 b/min). The W had the highest mean maximum HR (213m), while the CA had the lowest maximum HR (207.9m).Outfield soccer players in the current study cover between 8241.5m and 10024.9m mean total distance, while the GK covers 4,7km mean total distance. The W covered the highest total distance (10024.9m), closely followed by the CM (9734.9m) and CA (9911.5m). The GK, on the other hand, covered the lowest total distance (4692.4m). The GK covered the highest walking distance (3361.6m) and lowest distance in every other movement classification. The CM covered the highest jogging distance (5009.3m), while the CA covered the highest running distance (936.5m). The W covered the highest sprinting distance (258.4m), closely followed by the CA (175.2m). The CM had the highest total player load (1044.5au), player load per meter (0.107au/m), and player load per minute (11.085au/min), whereas the GK had the lowest player load in all categories. Conclusions: Based on player load and mean HR, it appears that the CM experiences a greater physiological demand than all the other positions on the field, while the GK experiences the lowest physiological demand. Training the CM, therefore, should focus on improving aerobic capacity to ensure readiness for the in-match rigours of the position. The total distance covered by the W suggests that the W experiences the highest physical demand among all positions. Since the W covers the highest sprinting distance among all positions, training regimens should focus on improving the W’s anaerobic capacity and repeated sprint ability to prepare the W for the high-intensity demands associated with the position. When using these results as an aid in the design of conditioning programmes, coaches and trainers are advised to consider that this study adds to a limited number of studies conducted on South African soccer. Furthermore, the current study was conducted in the second division of South African soccer. As a result, comparisons with studies from other countries should be made with utmost caution, particularly owing to differences in performance standards, as well as climatic and other environmental differences.
Open Access
Physical activity demands of golf
(University of the Free State, 2018-12) Brink, Tania Kristel; Schoeman, Riaan
Introduction: Golf is quite challenging in terms of the physical demands that it places on the body throughout a round of golf, and even more so during a golf tournament, due to the repetitive action. Understanding the fitness characteristics inherent in playing golf can supply prosperous advantages to golf players, including a better and more productive swing as well as improved body mechanics. Objectives: The purpose of the study is to quantify the demands and load being placed on golf players, especially during tournaments, and therefore to assist them with a better construction of their conditioning programmes during golf practice. The study also aimed to determine the distance covered, work to rest ratios, and frequency of movements in golf. Methods: GPS data on a total of twelve (12) amateur golf players were collected and a total of forty rounds of golf (18 holes) were analysed for the study. Therefore, a total of forty (40) GPS data sets (player rounds) were analysed (equivalent to 720 holes were recorded). Minimax X4 Catapult GPS units as well as a Polar HR monitors and chest straps was used to determine the physiological demands on golf players. The variables recorded are distances covered, player load, the maximal velocity during the round, and heart rate (HR) response. Players were categorised according to their handicap - handicap<0, handicap=0 and handicap>0. The handicap categories were compared with respect to selected activity variables using a linear mixed model with handicap category (3 levels) as fixed effect, and player as random effect. Fitting player as random effect accommodated potential correlation of the data collected from the same player. Based on this linear mixed model, the mean values (of the activity variable) for each handicap category were estimated, together with their standard errors. Furthermore, the pairwise mean differences between handicap categories were estimated, together with 95% confidence intervals (CIs) for the mean differences and P values associated with the null-hypothesis of zero mean difference between the pair of handicap categories in question. Results: The mean value for players with a handicap below zero has the lowest playing duration (<0: = 4.32 hours) in relation to the players with the handicap equal to zero (=0: = 4.71 hours) with a handicap above zero (>0: = 4.88 hours). The total distance covered by players with the handicap below zero (<0: = 10.82km) was the furthest, compared to players with a handicap equal to zero (=0: = 10.52km) as well as player with a handicap above zero (>0: = 10.42km). Total player load was the highest for players with a below zero handicap (<0: = 606.67) followed by those with an above zero handicap (>0: = 587.05) and players with handicaps equal to zero (=0: = 583.56). Results also show that players with a handicap above zero (>0: = 2.02) has the lowest player load per minute value. Player load per kilometre was highest amongst players with a handicap below zero (<0: = 56.32) followed by players with handicaps above zero (>0: = 55.61). Below zero handicap (<0: = 42.52) players covered the longest distance per minute of all players. Players with a handicap below zero (<0: = 3.24) had the highest maximum velocity compared to players with handicaps equal to zero (=0: = 2.87), followed by players with handicaps above zero (>0: = 2.73). Significant differences between the players with a handicap below zero and players with a handicap above zero for total duration (p=0.0194) and meters per minute (p=0.021) can be observed. Conclusions: The study reveals the physical profile of and physical demands on amateur golf players and indicates differences between the various handicaps of golf players. These findings emphasise the differences in amateur players regarding handicaps for the load, duration, and distance placed on the players. Coaches and conditioning coaches must implement the findings of the study to develop sport-specific, and more importantly, handicap-specific conditioning programmes.
Open Access
Randomised crossover trial of m. gluteus maximus and m. gluteus medius activation during rehabilitation exercises in female hockey players
(University of the Free State, 2020) Coetzee, Daretha; Coetzee, Frederik; Sinclair, Colleen
Introduction: Various researchers have focused on the activation capabilities of the gluteal muscles during different commonly used rehabilitation exercises. However, there is currently a lack of research in examining body weight rehabilitation exercises that elicit the highest percentage maximal voluntary isometric contraction (%MVIC) for both the m. gluteus maximus (mGmax) and m. gluteus medius (mGmed) in a high-performance athletic population. Field hockey predominantly requires maintaining a forward flexed posture, which places excessive stress on the lumbar spine of the players. Hence, it is necessary to assess the muscles that support the lumbar spine, especially the muscles that surround the hip, in order to prescribe strengthening exercises for this population. Knowledge of the percentage activation of the mGmax and mGmed elicited during body weight rehabilitation exercises may result in more specific exercise programme prescription during prehabilitation and the later stages of rehabilitation for high-performance female field hockey players. Objectives: The aim of the study was first to establish which commonly prescribed body weight rehabilitation exercises from previous studies produced greater than 61%MVIC for both the mGmax and mGmed. Hereafter, the study examined the exercises that fall into this category to determine which exercise will elicit the highest %MVIC, defined as the peak normalised sEMG signal amplitude, in high-performance female field hockey players of the University of the Free State (UFS). Methods: Surface electromyography (sEMG) was used to record the muscle activation of the mGmax and mGmed of four (4) body weight rehabilitation exercises on twenty-six (26) highperformance female field hockey players of the UFS. The %MVIC activation data of both the mGmax and mGmed were analysed using a three-way ANOVA, with ‘participant’, ‘period’ and ‘exercise’ as categorical variables in the model. Point estimates for the mean %MVIC for each exercise were reported, as well as point estimates, 95% confidence intervals (CIs) and p-values for the pairwise differences in peak %MVIC between the four body weight rehabilitation exercises. For each variable analysed, the overall F-test for the four body weight rehabilitation exercises is reported, as well as the partial effect size measure for ANOVA. Results: The mean age of the participants was 20.15±1.59 years, the mean height was 164±0.07cm, mean body mass was 64.72±10.21kg, and mean BMI was 23.87±2.92kg.m². Side-plank hip abduction with dominant leg on bottom generated a 124.61±7.94%MVIC of the mGmax and a 126.07±14.16%MVIC of the mGmed. Side-plank hip abduction with dominant leg on top generated a 124.33±8.63%MVIC of the mGmax and a 124.52±11.37%MVIC of the mGmed. The single-leg squat generated a 125.65±10.13%MVIC of the mGmax and a 126.30±12.89%MVIC of the mGmed. Plank with hip extension generated a 122.73±9.37%MVIC of the mGmax and a 125.04±13.14%MVIC of the mGmed. Concerning the mGmax, there was no significant difference found in activation when sideplank hip abduction with dominant leg on bottom was compared to side-plank hip abduction with dominant leg on top (p=0.8475, d=0.28), the single-leg squat (p=0.4807, d=-1.03) and plank with hip extension (p=0.2000, d=1.88). Furthermore, no significant difference was found when side-plank hip abduction with dominant leg on top was compared to the singleleg squat (p=0.3685, d=-1.31) and plank with hip extension (p=0.2770, d=1.60). However, there was a significant difference between the single-leg squat and plank with hip extension (p=0.0487, d=2.91). Concerning the mGmed, there was no significant difference in activation when side-plank hip abduction with dominant leg on bottom was compared to the side-plank hip abduction with dominant leg on top (p=0.3272, d=1.54), the single-leg squat (p=0.8837, d=-0.23) and plank with hip extension (p=0.5134, d=1.03). Furthermore, no significant difference was found when side-plank hip abduction with dominant leg on top was compared to the single-leg squat (p=0.2606, d=-1.77) and plank with hip extension (p=0.7437, d=-0.52) or between the single-leg squat and plank with hip extension (p=0.4240, d=1.26). When the exercise effect is combined, the four body weight rehabilitation exercises did not significantly affect either mGmax (p=0.2558) or mGmed (p=0.6285) activation. Conclusion: The four body weight rehabilitation exercises examined by the study generated very similar %MVIC activation of the mGmax and mGmed in high-performance female field hockey players. This research enables practitioners to apply evidence-based practice into programme prescription. Implementation of the findings of the current study could result in significant benefits during prehabilitation, injury prevention programmes and the later stages of rehabilitation for high-performance female field hockey players. The conditioning coach stands to benefit, especially given that these exercises can be executed on the playing pitch as part of a warm-up without the need for any equipment.