ABSTRACT
Children show different physiological reactions during and after short-duration, high-intensity exercise when compared to adults[1]. Many authors have observed reduced muscle and blood lactate concentrations in children after maximal aerobic bouts or after progressive exercise until exhaustion[2, 3]. Similarly the catecholamine concentrations in blood, after progressive exercise to exhaustion, seem to be lower in children than in adults[4, 5]. However, the data describing differences in the sympathetic activity of children and adults during maximal exercise, is contradictory[6], Little information is available concerning the adaptations in the purine nucleotide metabolism essential for transforming chemical energy into mechanical work, after specific anaerobic training[7]. Furthermore, as far as the author is aware, nothing is known about purine nucleotide metabolism and muscle ammonia formation during anaerobic activity in children.
