Abstract

An athlete's dietary and supplement strategies can provide a valuable contribution to overall sport performance. Personalized nutrition for athletes and fitness enthusiasts aims to optimize nutrition status, body composition, and exercise performance by tailoring dietary recommendations to an individual's genetic profile. Sport dietitians and nutritionists have long been modifying the one-size-fits-all general population dietary guidelines in order to accommodate the needs of athletes. In general, high-performance sport requires the addition of carbohydrates to fuel training and higher protein intakes to repair muscle. However, generic recommendations still remain with regard to micronutrients, food intolerances, bone health, risk of muscle damage, and various other performance-related nutritional factors that deserve consideration. Genetic variation is known to affect absorption, metabolism, uptake, utilization, and excretion of nutrients and food bioactives, which can alter the activity of metabolic pathways. Nutrigenomics and nutrigenetics are experimental approaches that use genomic information and genetic testing technologies to examine the role of individual genetic differences in modifying an athlete's response to nutrients or substances in foods and supplements. With the exception of caffeine, there have been few randomized, controlled trials examining the effects of genetic variation on performance in response to dietary interventions or ergogenic aids. However, there is a growing foundation of research linking gene–diet interactions on biomarkers of health and nutritional status. This means that reaching specific targets for an athlete's nutritional status to optimize health and body composition will in turn beneficially affect exercise and sport performance. These concepts and their actions form the basis from which the field of sport nutrigenomics continues to develop. Here we review the current science that associates genetic modifiers with foods, nutrients and ergogenic aids, and their impact on athletic performance.