Intramuscular determinants of the ability to recover work capacity above critical power.
Publication/Presentation Date
4-1-2015
Abstract
PURPOSE: The primary purpose of this investigation was to compare the recovery of the W' to the recovery of intramuscular substrates and metabolites using (31)P- and (1)H-magnetic resonance spectroscopy.
METHODS: Ten healthy recreationally trained subjects were tested to determine critical power (CP) and W' for single-leg-extensor exercise. They subsequently exercised in the bore of a 1.5-T MRI scanner at a supra-CP work rate. Following exhaustion, the subjects rested in place for 1, 2, 5 or 7 min, and then repeated the effort. The temporal course of W' recovery was estimated, which was then compared to the recovery of creatine phosphate [PCr], pH, carnosine content, and to the output of a novel derivation of the W' BAL model.
RESULTS: W' recovery closely correlated with the predictions of the novel model (r = 0.97, p = 0.03). [PCr] recovered faster [Formula: see text] than W' [Formula: see text] The W' available for the second exercise bout was directly correlated with the difference between [PCr] at the beginning of the work bout and [PCr] at exhaustion (r = 0.99, p = 0.005). Nonlinear regression revealed an inverse curvilinear relationship between carnosine concentration and the W' t 1/2 (r (2) = 0.55).
CONCLUSION: The kinetics of W' recovery in single-leg-extensor exercise is comparable to that observed in whole-body exercise, suggesting a conserved mechanism. The extent to which the recovery of the W' can be directly attributed to the recovery of [PCr] is unclear. The relationship of the W' to muscle carnosine content suggests novel future avenues of investigation.
Volume
115
Issue
4
First Page
703
Last Page
713
ISSN
1439-6327
Published In/Presented At
Skiba, P. F., Fulford, J., Clarke, D. C., Vanhatalo, A., & Jones, A. M. (2015). Intramuscular determinants of the ability to recover work capacity above critical power. European journal of applied physiology, 115(4), 703–713. https://doi.org/10.1007/s00421-014-3050-3
Disciplines
Business Administration, Management, and Operations | Health and Medical Administration | Management Sciences and Quantitative Methods
PubMedID
25425258
Department(s)
Administration and Leadership
Document Type
Article