Exercise physiologists have found some differences between
athletic performance in the morning and later in the day. Many
of these differences are attributed to the body’s circadian
rhythms—24-hour cycles that control physical and behavioral
factors such as sleep, mood, metabolism, and body temperature.
These cycles are driven by signals from the brain and other
organs in the body. If you are looking to improve your fitness,
lose weight, enhance your mood, and/or just have fun, the best
time to exercise is the time that you will consistently do it.
The differences measured in research labs will likely have
little bearing on your enjoyment and fitness level. In fact,
researchers who looked at decreased anxiety and improved mood
found that exercise at any time of day was equally as effective.
For more competitive athletes, the time of day you do your most
vigorous workouts does appear to have an effect. Researchers
believe that workouts are most productive when body temperature
is at its highest in the late aft