When Is the Best Time to Exercise?

When Is the Best Time to Exercise?

Some people have such busy schedules that finding any time during the day to exercise seems like a miracle. Others, however, have more flexibility to choose when they exercise. If you fall in the latter group, is there an ideal time of the day to work out?


When Is the Best Time to Exercise?:

A lot of research shows that exercising between 2:00 pm and 6:00 pm is ideal. Your body’s circadian rhythm causes consistent changes in your body throughout the day. Research shows that the optimal time for exercise is roughly when your body temperature is at its highest point, which occurs in the late afternoon. Here’s some of the research highlights:

  • Lung function is improved in the late afternoon. One study tested participants’ lung function at one hour intervals from 8:00 am to 5:00 pm. They found that lungs performed at their maximal capacity between 3:00 pm and 5:00 pm (17.6% greater than at noon).
  • Optimal strength and hypertrophy (muscle growth) gains have been found to occur in the late afternoon.
  • There is also an improvement in hand-eye coordination, an increase in flexibility and a decline in injury in the later afternoon.
  • This also translates into actual performance. Another study found that swimmers had significantly faster times in late afternoon (6:00 pm) versus the morning (10:00 am). Their muscle strength, muscle power and vertical jump were also improved more in the late afternoon.
  • A review of 113 articles found that the best time for athletic performance is in the early evening.
  • A final meta analysis found that sleep is best when you exercise between 4 and 8 hours before bedtime. So, if you go to sleep at 10:00 pm, that conveniently corresponds to between 2:00 pm and 6:00 pm.

Over time, your body seems to adapt to the time of day you exercise. Studies have shown that [Vdot]O2 levels (a test of fitness that measures the amount of oxygen consumed per minute of running) were highest in the morning for people who trained in the morning and highest in the afternoon for people trained in the afternoon. This shows the benefits of sticking to a schedule and the of training at the same time that you have any sort of athletic event to make sure you’re performing near your peak at that time.



It’s clear that performance is best in the later afternoon. If you exercise in the afternoon you’ll be able to run further and lift more weight. However, the most important thing is to exercise no matter what the time. So if morning fits best in your schedule, don’t feel at all bad about it. It’s easier to stick to a morning routine for many people. Otherwise, try working out in the afternoon to see how you like it!



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Kubitz, Karla A., et al. “The effects of acute and chronic exercise on sleep.”Sports Medicine 21.4 (1996): 277-291.

Medarov, Boris I., Valentin A. Pavlov, and Leonard Rossoff. “Diurnal variations in human pulmonary function.” International journal of clinical and experimental medicine 1.3 (2008): 267.

Pallarés, Jesús G., et al. “Circadian rhythm effects on neuromuscular and sprint swimming performance.” Biological Rhythm Research 45.1 (2014): 51-60.

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