The recovery of repeated-sprint exercise is associated with PCr Resynthesis, while muscle pH and EMG amplitude remain depressed
Publication Details
Hamer, P.,
Mendez-Villanueva, A.,
Edge, J.,
Suriano, R.,
&
Bishop, D.
(2012).
The recovery of repeated-sprint exercise is associated with PCr Resynthesis, while muscle pH and EMG amplitude remain depressed.
Plos One, 7 (12), 1-10.
https://doi.org/10.1371/journal.pone.0051977
Abstract
The physiological equivalents of power output maintenance and recovery during repeated-sprint exercise (RSE) remain to be fully elucidated. In an attempt to improve our understanding of the determinants of RSE performance we therefore aimed to determine its recovery following exhaustive exercise (which affected intramuscular and neural factors) concomitantly with those of intramuscular concentrations of adenosine triphosphate [ATP], phosphocreatine [PCr] and pH values and electromyography (EMG) activity (a proxy for net motor unit activity) changes. Eight young men performed 10, 6-s all-out sprints on a cycle ergometer, interspersed with 30 s of recovery, followed, after 6 min of passive recovery, by five 6-s sprints, again interspersed by 30 s of passive recovery. Biopsies of the vastus lateralis were obtained at rest, immediately after the first 10 sprints and after 6 min of recovery. EMG activity of the vastus lateralis was obtained from surface electrodes throughout exercise. Total work (TW), [ATP], [PCr], pH and EMG amplitude decreased significantly throughout the first ten sprints (PPP
Keywords
electromyography, electrodiagnosis, phosphocreatine, creatine, phosphates