Effects of a Short Work/Shorter Rest Intermittent Exercise on Muscle Metabolic Status, VO2, Hemoglobin Saturation and Performance, PhD, 2010, Glen Robert Belfry, Exercise Science, University of Toronto.
Abstract
Many sports require short duration work periods and short duration rest periods (INT). This dissertation examines the engagement of aerobic and anaerobic energy systems in acute exercise with brief (10 seconds) work and recovery (5 seconds) and the effect of chronic exposure on those systems. The differences between INT and continuous exercise (CONT) of deoxygenated hemoglobin saturation (ΔHHb), the pattern of breath-by-oxygen uptake (VO2) and muscle metabolic status, including, [Pi], [Pi]/[PCr], and [H+] were studied in young healthy adults. The physiological and performance responses to a four week, 12 session cycle ergometer training regime of the CONT and INT protocols were observed. Fluctuations in VO2, ∆HHb, [PCr], and [H+] were observed within the work : recovery duty cycle of INT. Fluctuations of VO2, ΔHHb, and [PCr] may be a function of the priming effects of previous high intensity exercise, inhibition at the locus of metabolic control, and elevated blood flow over the recovery-work transitions. Fluctuations in oxidative phosphorylation were associated with concurrent fluctuations in [PCr]. [Pi] and [PCr] were greater in INT vs CONT, whereas no differences were observed for [H+] between conditions. Reduced [PCr] may be the most appropriate indicator of metabolic stress, not increased [Pi] or [H+]. Similar improvements in aerobic power were observed for CONT and INT training, whereas anaerobic performance was enhanced post-INT training. Collectively the findings indicate that a unique INT exercise protocol facilitates increased muscle blood flow versus continuous exercise, the temporal association of muscle metabolic status, ΔHHb, and pulmonary VO2 with work rate, the apt use of [PCr] as a proxy for metabolic stress, and when this unique INT bout is utilized as a training protocol, adaptations in both aerobic and anaerobic metabolism will occur.
| Identifer | oai:union.ndltd.org:TORONTO/oai:tspace.library.utoronto.ca:1807/26501 |
| Date | 16 March 2011 |
| Creators | Belfry, Glen Robert |
| Contributors | Thomas, Scott |
| Source Sets | University of Toronto |
| Language | en_ca |
| Detected Language | English |
| Type | Thesis |
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