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Updated: Jul 16, 2026

Determining the Contribution of the Energy Systems During Exercise
Published on: March 20, 2012
Influence of time of day on anaerobic capacity
P D Marth1, R R Woods, D W Hill
1Department of Kinesiology, University of North Texas, Denton 76203-1337, USA.
Abstract:
12 volunteers performed exhaustive exercise tests in the morning and afternoon. Paired-means t tests indicated that anaerobic capacity, as reflected by maximal accumulated oxygen deficit, was 26% higher (p < .01) in the afternoon than in the morning. VO2max appeared higher and VO2 kinetics seemed faster in the afternoon, but differences did not attain statistical significance. Thus, the time of day affects anaerobic capacity and may influence other responses to exercise.
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