Muscle lactate, ATP, and CP levels

1972.-r “ 1 he study was performed on 14 subjects before, after 3, and after 7 months of physical conditioning. At each occasion muscle biopsies were taken at rest and after submaximal and maximal work loads on which determinations of muscle ATP, CP, glycogen, and lactate were performed. Maximal oxygen uptake increased from 3.3 to 3.7 and 4.1 L min-I, respectively, and no significant change in mean body weight was observed. The conditioning program increased the resting A’TP concentration in the muscle, while CP concentration was unaffected. The physical conditioning also resulted in less pronounced phosphagen (ATP + CP) de-pletion at the same absolute submaximal work load but unchanged values were found at identical relative work loads. After training muscle lactate concentration was significant] y lower at t he same absolute and relative submaximal work loads. At maximal work lactate concentration was not increased. At the same absoXut