Muscle Metabolites with Exhaustive Static Exercise of Different Duration

Concentrations of ATP, CP, glycogen and lactate were determined in the lateral portions of the thigh at rest and at different percents (75, 50, 25 and 10 %) of the individual maximal voluntary isometric contraction (MVC). Endurance times were 0.5, 1.6, 5.8 and 38.7 min respectively. A phosphagen depletion of 15 mmol x kg ‐1 wet muscle and a lactate accumulation of 20 mmol x kg ‐1 was obtained only with the 50 % MVC which is similar to what is observed with short time exhaustive bicycle exercise. At both higher and lower intensities phosphagen depletion and lactate accumulation were less.