Adaptive Characteristics of Skiers with Different Types of Energy Supply of Skeletal Muscles to Graded Exercise and Athletic Training

Thirty-five skiers with different types of energy supply to skeletal muscle were studied over a one-year training cycle. The adaptive characteristics of the adolescent boys were assessed by Baevskii's index of stress in the body's regulatory systems (stress index) caused by exercise at high workloads (3 and 6 W/kg); by the physiological cost of the exercise; by the time to exhaustion at a moderate workload (1.5 W/kg) in a bicycle ergometer test; and by athletic results. The stress index, the physiological cost of exercise and their changes over a one-year training cycle were clearly correlated with the type of energy production. It was suggested that training brings into play genetically determined adaptive programs and that an increase in the functional capabilities during ontogenesis is under control of the genome and mainly determined by individual and typological features of the body.