Study of the energy metabolism indices and those of acid-alkaline balance in highly trained sportsmen and in the beginners revealed a dependence of the organism biochemical changes on intensity of physical loads, thus indicating a direct relationship between the energy metabolism rate and the degree of the athletes organism's adaptation. The study revealed fluctuations of regenerative processes during 24 hours and specified the contribution of each energy source to energy production under a variety of physical load. A growing adaptation of the athlete organism to physical loads results in a stronger correlation ties among separate indices of the energy metabolism.