Hans Braun, Hans Geyer and Karsten Koehler
Hans Braun, Judith von Andrian-Werburg, Wilhelm Schänzer and Mario Thevis
Purpose: To investigate energy intake, energy expenditure, and the nutritional status of young female elite football players using 7-day food and activity records and blood parameters. Methods: A total of 56 female elite football players [14.8 (0.7) y] completed the requested food and activity protocols. Misreporting was assessed by the ratio of energy intake to energy expenditure. The food records were analyzed concerning energy and macronutrient and micronutrient intakes, and energy expenditure was calculated using predictive equations. Hematological data and 25-hydroxyvitamin D serum concentrations were determined. Results: Mean energy intake was 2262 (368) kcal/d [40.5 (7.0) kcal/kg/d] and estimated EE averaged 2403 (195) kcal/d. Fifty-three percent of the players exhibited an energy availability <30 kcal/kg lean body mass; 31% of the athletes consumed <5 g/kg carbohydrates and 34% consumed <1.2 g/kg proteins. A large proportion of players (%) had intakes below the recommended daily allowance of folate (75%), vitamin D (100%), iron (69%), and calcium (59%). Ferritin and 25-hydroxyvitamin D serum levels were below the recommendations of 59% and 38%, respectively. Conclusions: A remarkable number of players failed to meet the energy balance and the recommended carbohydrate and protein intakes. Low iron and 25-hydroxyvitamin D serum levels were observed showing a suboptimal nutrition status of some young female football players. As a consequence, strategies have to be developed for a better information and application of sport nutrition practice among young female football players.
Hans Braun, Karsten Koehler, Hans Geyer, Jens Kleinert, Joachim Mester and Wilhelm Schänzer
Little is known about the prevalence and motives of supplement use among elite young athletes who compete on national and international levels. Therefore, the current survey was performed to assess information regarding the past and present use of dietary supplements among 164 elite young athletes (16.6 ± 3.0 years of age). A 5-page questionnaire was designed to assess their past and present (last 4 weeks) use of vitamins, minerals, carbohydrate, protein, and fat supplements; sport drinks; and other ergogenic aids. Furthermore, information about motives, sources of advice, supplement sources, and supplement contamination was assessed. Eighty percent of all athletes reported using at least 1 supplement, and the prevalence of use was significantly higher in older athletes (p < .05). Among supplement users, minerals, vitamins, sport drinks, energy drinks, and carbohydrates were most frequently consumed. Only a minority of the athletes declared that they used protein/amino acids, creatine, or other ergogenic aids. Major motives for supplement use were health related, whereas performance enhancement and recommendations by others were less frequently reported. Supplements were mainly obtained from parents or by athletes themselves and were mostly purchased in pharmacies, supermarkets, and health-food stores. Among all athletes, only 36% were aware of the problem of supplement contamination. The survey shows that supplement use is common and widespread among German elite young athletes. This stands in strong contrast to recommendations by leading sport organizations against supplement use by underage athletes.
Karsten Koehler, Frank Huelsemann, Markus de Marees, Bjoern Braunstein, Hans Braun and Wilhelm Schaenzer
During prolonged periods of high energy expenditure (EE), restricted food intake can lead to a loss of body mass. This case study describes the preexpedition support for an unsupported 3-wk crossing of the Atacama Desert in Chile. The goals were to simulate the energy requirements of walking under varying conditions and to predict energy intake and EE to evaluate whether the expected weight loss was in acceptable limits. The expeditionist (male, 35 yr, 197 cm, basal weight 80 ± 0.5 kg) was a well-trained endurance athlete with experience of multiple expeditions. During the simulation, he walked on a treadmill at speeds of 2–7 km/hr under varying conditions of inclination (0%, 7.5%), backpack weight (0 kg, 30 kg), and altitude (sea level, simulated altitude of 3,500 m). Under all conditions, the lowest EE was observed at 5 km/hr. Based on the simulation data, we predicted an average EE of 4,944 kcal/day for the expedition. Because energy intake was restricted to 2,249 kcal/day, we expected the expeditionist to lose considerable weight and consequently advised him to gain 5 kg of body-fat reserves. During the actual desert crossing, he covered a distance of 26 ± 7 km/day at an average speed of 3.8 ± 0.4 km/hr. Daily EE (4,817 ± 794 kcal/day) exceeded energy intake (1,771 ± 685 kcal/day), and the negative energy balance was in agreement with the actual weight loss of 10.5 kg, which was most notable in the lower trunk.