Every athlete has a preferred exercise time. Previous studies have shown that the circadian rhythm has a significant effect on exercise performance. For endurance exercise, performance may vary as much as 26% and for strength exercise, performance may vary as much as 41% throughout the day. Short-duration maximal exercises (i.e. less than 1 min – e.g. all-out sprints, maximal jumps or isometric contractions) comprise both modes of exercise and are characterized by higher anaerobic energy contributions than than longer duration exercises. Thus short-duration maximal exercises may be a better model to determine the effect of the circadian rhythm on exercise performance.
Researchers found there was a strong diurnal influence with exercise performance, peaking between 4 and 10 pm. This obviously is bad news for morning exercisers and early to bed sleepers. However, one of the more interesting findings of this study, is that other factors can modulate or override the circadian effect. These include:
Exposure to moderately warm and humid environment
Active warm up protocols
Warming up while listening to music
Long periods of training at a specific time of day
This type of research is opening new areas on how to maximize exercise performance and it indicates that mood and motivation play an essential role in determining overall exercise performance as well as our physiological status.