Nutrition and Genes: Molecular Mechanisms of Metabolic Adaptation to Physical Activity

Individual sensitivity to physical exercise is considered a multifactorial phenomenon with a significant contribution from genetic determinants. This study systematizes data on genes influencing endurance, strength, recovery, and metabolic adaptation to training. The mechanisms of action of genes associated with the regulation of the renin-angiotensin system, muscle fiber structure, mitochondrial energy metabolism, fatty acid oxidation, and angiogenesis are described. Variations in the angiotensin-converting enzyme gene are shown to be associated with differences in endurance and speed-strength characteristics. Polymorphisms in genes encoding alpha-actinin, mitochondrial uncoupling proteins, and energy metabolism enzymes determine muscle fiber type, aerobic exercise efficiency, and fatigue levels. Particular attention is paid to the relationship between genetic variations and the body's nutritional needs. It has been shown that aerobic genotypes (for example, those with high UCP2/UCP3 expression or the C allele of the PPARD gene) are characterized by increased dependence on fat metabolism, while anaerobic variants (ACTN3 polymorphism, low AMPD1 activity) require increased carbohydrate and protein intake. Thus, genetic characteristics directly influence the priority selection of macronutrients for energy supply and recovery. The study also analyzes the risks associated with a genetic predisposition to metabolic disorders and overtraining and provides appropriate dietary recommendations for their minimization. The ethical aspects and potential consequences of the use of genetic technologies in sports are considered, including the risks of using growth genes and myostatin inhibitors for gene doping. The need for a strict distinction between therapeutic gene therapy and unacceptable performance-enhancing methods is emphasized. In conclusion, the feasibility of integrating genetic information for personalizing training programs and nutritional support is substantiated, which allows for increased adaptation efficiency, performance, and reduced health risks for athletes.