ENERGY AND MACRONUTRIENT INTAKE OF SWISS ELITE ATHLETES

Abstract

Dietary practices of Swiss elite athletes are only poorly described. The nutritional intake of 127 athletes - most of them owning an elite athlete certification of the Swiss Olympic Association - was therefore assessed between 1996 and 1999. The athletes belonged to sports types ranging from triathlon to bobsleigh. During an average of seven days, the nutrition of 45 female (F; mean and standard deviation age 23 ± 5 y, body mass 58 ± 9 kg, body height 167 ± 8 cm) and 82 male athletes (M; 25 ± 5 y, body mass 76 ± 12, body height 181 ± 7 cm) was recorded according to standard methods (weighing protocols). Additionally, the energy expenditure was calculated for the time frame of the dietary recording by means of activity protocols. The database used for nutrient intake analysis was the Swiss version of the German Federal Food Key and the energy expenditure was calculated as the resting energy expenditure (standard formula) multiplied with a factor for the individual physical activity level. The energy intake was 9.5 ± 3.2 MJ for F and 13.8 ± 3.3 MJ for M, respectively. The energy expenditure was 12.3 ± 2.2 MJ and 13.0 ± 3.0 MJ for F and M, respectively, resulting in a slightly positive balance for M and a massive negative balance for F. The energy percentage derived from the macronutrients was: F: carbohydrates 55%, fat 27%, protein 18% and alcohol 0%; M: carbohydrates 52%, fat 28%, protein 19% and alcohol 1%. For carbohydrates and protein this resulted in an intake relative to the body mass of 5.5 g/kg and 1.4 g/kg for F and 5.9 g/kg and 1.7 g/kg for M, respectively. The fluid intake was 3.0 ± 1.3 L/d for F and 3.8 ± 1.2 L/d for M. The most striking result was the negative energy balance of about 3 MJ with the female athletes, which would correspond in a hypothetical body fat loss of about 35 kg per year. Since a negative energy balance was reported in 77% of the female compared to 49% of the male athletes, this indicates a probably gender-specific phenomenon of either nutritional underreporting, and/or undereating, and/or real negative energy balance of the female athletes.