Phosphocreatine recovery overshoot after high intensity exercise in human skeletal muscle is associated with extensive muscle acidification and a significant decrease in phosphorylation potential

• Published in: The journal of physiological sciences 2010-09, Vol.60 (5), p.331-341
• Main Authors: Zoladz, Jerzy A., Korzeniewski, Bernard, Kulinowski, Piotr, Zapart-Bukowska, Justyna, Majerczak, Joanna, Jasiński, Andrzej
• Format: Article
• Language: English
• Subjects: 31P NMR spectroscopy; Acidosis; Acidosis - metabolism; Adult; Body Mass Index; Exercise; Humans; Leg - physiology; Male; Muscle, Skeletal - chemistry; Muscle, Skeletal - metabolism; Original Paper; Parallel activation; PCr overshoot; Phosphocreatine - analysis; Phosphocreatine - metabolism; Phosphorylation; Skeletal muscle; Young Adult
• ISSN: 1880-6546; 1880-6562
• DOI: 10.1007/s12576-010-0101-3

The phosphocreatine (PCr) recovery overshoot in skeletal muscle is a transient increase of PCr concentration above the resting level after termination of exercise. In the present study [PCr], [ATP], [Pi] and pH were measured in calf muscle during rest, during plantar flexion exercise until exhaustion and recovery, using the 31P NMR spectroscopy. A significantly greater acidification of muscle cells and significantly lower phosphorylation potential (ΔGATP) at the end of exercise was encountered in the group of subjects that evidenced the [PCr] overshoot as well as [ADP] and [Pi] undershoots than in the group that did not. We postulate that the role of the PCr overshoot-related transiently elevated [ATP]/[ADPfree] ratio is to activate different processes (including protein synthesis) that participate in repairing numerous damages of the muscle cells caused by intensive exercise-induced stressing factors, such as extensive muscle acidification, a significant decrease in ΔGATP, an elevated level of reactive oxygen species or mechanical disturbances.