Changes in metabolic efficiency in skilled athletes during intense exercise

Abstract

Summary The body’s predominant choice of substrates and the rate of their oxidation in the work ing muscle are largely influenced by physical activity intensity. The higher the intensity of work, the more important role in energy supply processes are played by carbohydrates. It is suggested that the ability to most effectively use fat as an energy substrate at rest and during exercise allows athletes to save carbohydrates to perform high-intensity work. This study inves tigated the efficiency of metabolism in skilled athletes at rest and during the exercise of increas ing intensity. 99 body composition assessments (via bioelectrical impedance) and 99 incre mental exercise tests using a gas analysis system were performed in 90 male national- and international-level athletes (age 16-35 y.o.) of sports related to endurance and combat sports. The respiratory exchange ratio in skilled athletes at rest significantly correlates with the val ues of respiratory exchange ratio when reaching the anaerobic threshold ((r = 0.52, р ≤ 0,05)) and respiratory exchange ratio when reaching the maximum oxygen consumption ((r = 0.52, р ≤ 0,05)) and with the maximum oxygen consumption (r = -0.26, р ≤ 0,05). The oobtained data shows that efficient resting metabolism creates the preconditions for more efficient use of energy substrates during intense muscle activity. The respiratory exchange ratio is an informative indicator of the efficiency of metabolism, which can be used in the com plex control of the functional condition of the athlete.