RESUMO
In a recent paper entitled "A genetic-based algorithm for personalized resistance training", Jones et al. [1] presented an algorithm of 15 performance-associated gene polymorphisms that they propose can determine an athlete's training response by predicting power and endurance potential. However, from the design of their studies and the data provided, there is no evidence to support these authors' assertions. Progress towards such a significant development in the field of sport and exercise genomics will require a paradigm shift in line with recent recommendations for international collaborations such as the Athlome Project (see www.athlomeconsortium.org). Large-scale initiatives, involving numerous multi-centre and well-phenotyped exercise training and elite performance cohorts, will be necessary before attempting to derive and replicate training and/or performance algorithms.
RESUMO
BACKGROUND: Bioelectrical impedance analysis would be a more practical tool to measure body composition in clinical settings, dietetic practice and epidemiological studies if patients/subjects did not have to fast before measurements. The present study assessed whether the ingestion of food or drink had any biologically significant effect on bioimpedance measurements and body composition by the foot-to-foot method. METHODS: Fifty-five healthy adults [30 males and 25 females; mean (SD) age 27.7 (7.1) years; mean (SD)body mass index 24 (3.8) kg m(-2)] were randomly assigned to a 2-day food trial (high-fat meal or high-carbohydrate meal) or a 2-day drink trial (water or high electrolyte drink). Body composition measurements were carried out in the fasting state, immediately after meal consumption and every 30 min for 2 h by the foot-to-foot single frequency bioimpedance technique. RESULTS: Bioimpedance increased significantly after the ingestion of food and fluid, although the changes were small. The electrolyte drink, high-fat and high-carbohydrate meals significantly increased the percentage body fat and fat mass. In all cases, the median percentage changes from baseline were approximately 1% in body fat percentage units. CONCLUSIONS: Although there were statistically significant changes in body composition estimates after food or drink consumption, these were small and within the imprecision of the impedance technique, and so are unlikely to be of clinical significance. The present study suggests that impedance measures of body fatness in clinical settings do not require strict adherence to fasting, and this should increase the opportunities for clinical application.