Body composition, dietary intake and supplement use by swimmers at the High Performance Centre, Pretoria

English: The development of sports institutions and High Performance Centres are on the increase worldwide and also in South Africa. These hotels and ‘athlete villages’ can provide unsuitable food choices and lack of supervision may further encourage poor eating patterns among young swimmers. A swimmer’s diet needs to be adequate in the essential nutrients to support his energy expenditure during training, pre-competition, competition and recovery. The mean ages for elite swimmers fall into the stage of puberty; and this also has an influence on nutrient requirements. The body composition of a swimmer as well as the percentage body fat has a direct relationship with body drag, because body fat increases the resistance of the body in the water. Physiological adaptations of the body take place when an efficient training programme is followed in combination with adequate nutrition. The purpose of this study was to determine: a) the body composition (including the body mass index (BMI), percentage body fat, lean body mass (LBM), mid-arm muscle area (MAMA) and mid-upper arm fat area (MAFA) of swimmers, b) the energy, macronutrient and micronutrient content of the usual diet of swimmers (including the training, pre-competition, competition and recovery diet) and c) the use of supplements by swimmers. A descriptive study design was used for data gathering on demographics, anthropometrics, usual dietary intakes as well as information on the use of supplements. The study was done on the University of Pretoria club (TUKS) swimming team practising at the High Performance Centre in Pretoria. Anthropometrics included skin-fold measurements to predict percentage body fat and to calculate LBM (lean body mass); MUAC (mid upper arm circumference) to determine MAMA (mid arm muscle area) and MAFA (mid arm fat area). Demographical data with information on the use of supplements was obtained by a questionnaire, and the usual dietary intake data was obtained from food records. The data was then compared to the recommended amounts or the RDA (recommended dietary allowances) and AI (adequate intakes). The swimmers had an adequate BMI, a low percentage body fat level and greater proportion of LBM for muscular mass, which correlates with an ideal body composition profile for swimmers. The usual dietary intake (training, pre-competition, competition and recovery diet) was inadequate for most of the swimmers. Three of 12 males and all the female swimmers (n = 8) had an inadequate energy intake during training. Fifty percent of the swimmers had a lower CHO intake than recommended. These swimmers might have been at risk of not maintaining blood-glucose levels during training. Twelve out of 20 swimmers were not meeting their protein needs. The fat intake of 40 % of the swimmers was higher than recommended. Before competition all the swimmers had a lower CHO intake than recommended. They might not have had the beneficial effect of a high CHO diet before competition. The group had a high fat intake during competition. Ninety five percent of the swimmers had a lower CHO intake than recommended after competition. Most of the swimmers were at risk of not replenishing glycogen stores. Sixty five percent of the swimmers used supplements. A need for nutritional intervention was identified, focusing on the nutritional needs of a swimmer during training, pre-competition, competition and recovery.