A 31P MRS Study of the Effects of Exercise-Induced Acidosis on Phosphocreatine Recovery Kinetics in Three Muscle Groups in a Single Cohort of Human Subjects

Gwenael Layec¹, Emil Malucelli², Christophe Vilmen¹, David Manners², Kazuya Yashiro¹, Claudia Testa², Patrick J. Cozzone¹, stefano Iotti², David Bendahan¹

It is acknowledged that mitochondrial function can be assessed in vivo from PCr resynthesis during recovery period. Several studies have pointed out that end-of-exercise conditions could bias the characterization of mitochondrial function. The purpose of the present study was to analyze the relationship between end-of-exercise pH and PCr recovery rates in forearm, calf and thigh muscles in a single group of subjects in order to determine whether a common normalisation frame could be adopted for different muscles. Overall, our results clearly illustrate that, whatever the muscle investigated, low end-of exercise pH is systematically related to a slower PCr recovery kinetics.