Phosphocreatine recovery overshoot after high intensity exercise in human skeletal muscle is associated with extensive muscle acidification and a significant decrease in phosphorylation potential.
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], [P(i)] and pH were measured in calf muscle during rest, during plantar flexion exercise until exhaustion and recovery, using the (31)P NMR spectroscopy. A significantly greater acidification of muscle cells and significantly lower phosphorylation potential (DeltaG (ATP)) at the end of exercise was encountered in the group of subjects that evidenced the [PCr] overshoot as well as [ADP] and [P(i)] undershoots than in the group that did not. We postulate that the role of the PCr overshoot-related transiently elevated [ATP]/[ADP(free)] 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 DeltaG (ATP), an elevated level of reactive oxygen species or mechanical disturbances.
Zoladz
Jerzy A
JA
Department of Physiology and Biochemistry, University School of Physical Education-Kraków, Al. Jana Pawla II 78, 31-571, Krakow, Poland. wfzoladz@cyf-kr.edu.pl
Korzeniewski
Bernard
B
Kulinowski
Piotr
P
Zapart-Bukowska
Justyna
J
Majerczak
Joanna
J
Jasiński
Andrzej
A
D000138:Acidosis / Q000378:metabolism*; D000328:Adult; D015992:Body Mass Index; D015444:Exercise; D006801:Humans; D007866:Leg / Q000502:physiology; D008297:Male; D018482:Muscle, Skeletal / Q000737:chemistry / Q000378:metabolism*; D010725:Phosphocreatine / Q000032:analysis / Q000378:metabolism*; D010766:Phosphorylation; D055815:Young Adult
D010725:Phosphocreatine