Energy supply of muscular activity of five- to six-year-old children and complex assessment of physical working capacity

Abstract

A complex study of the physical working capacity of five- to six-year-old children (n = 106) was performed. It was found that the physical working capacity of preschool children at this age is determined by the following five major factors: (I) aerobic capacity, (II) anaerobic glycolytic working capacity, (III) absolute aerobic power, (IV) relative aerobic power, and (V) anaerobic alactic working capacity. Sex-related differences in some parameters reflecting the physical working capacity and fitness, characterizing the anaerobic alactic and anaerobic glycolytic productivity of the body were revealed. These differences are apparently related to an advanced development of anaerobic energy-supply mechanisms of girls compared to age-matched boys. The procedure of a complex assessment of the physical working capacity of five- to six-year-old children has been developed, which includes informative parameters characterizing the power and capacity of energy systems selected on the basis of results of factor analysis and expert assessment. A rapid procedure for a complex assessment of working capacity based on calculating the time during which a physical load (2 W/kg) can be sustained is proposed. The study showed that shifts in the intensity of physical activity within the optimal range resulted in multifold changes in its duration. Importantly, the duration of physical activity’s performance at an intensity of 175–180 bpm in children with a high working capacity is comparable to the maximum work duration at a heart rate of 140–145 bmp in preschool children with a low physical condition. Differences between children with high and low physical working capacity were found to increase with an increase in the physical load aerobicity. The physical working capacity of five- to six-year-old children can be differentiated best of all on the basis of aerobic capacity parameters. The enormous range of changes in the aerobic capacity parameters makes them especially valuable for characterizing the level of somatic health of preschool children. The results of this study were used to construct a nomogram for the determination of the allowable training load depending on its intensity and physical working capacity.