The best time to exercise for performance is around 6 pm, according to research on lung function, body rhythms, temperature, and hormone levels. People also were found put in more workout effort in afternoon exercise.
But morning is the best time to exercise if you want to stick with your exercise habit. Surveys show we are more likely to exercise at all if we do it first thing in the morning, before other distractions eat up our free time or give us an excuse to not exercise.
Morning Exercise - Pros and Cons
• If you want to be consistent in exercising, choosing morning exercise makes it easier to stick with your intention and get into a regular exercise habit.
• Morning workouts are less likely to be affected by disruptions in your schedule and everyday emergencies.
• If you find it hard to make time for exercise during the day, you can instead get up a little earlier in the morning to get in your workout.
• Moderate to vigorous exercise raises your heart rate and metabolism to burn more calories earlier in the day.
• The exercise afterglow can help you feel energized for hours.
• The increased blood flow through your brain helps improve your mental acuity for your daily tasks.
• A study found that morning exercise was better for sleep quality than exercising at other times of day.
• Make the most of the cool part of the day for outdoor exercise in summer - running, walking, etc.
• The air quality may be best in the morning.
• Are you training for a morning race or competition? Time-of-day specific training will let your body prepare, as well as get you into the routine you will need on race day.
• Body temperature is at its lowest 1-3 hours before awakening, making morning a time of naturally lower energy and blood flow.
• Warm-ups are very important in the morning, as your muscles have been dormant all night. Give yourself a warm-up period of at least five minutes of easy exercise before going into a higher intensity workout. Gentle stretching and flexibility exercises may also be good.
• Do you hate getting up early and working out? Choose a more enjoyable time of day and you will be more consistent with your exercise habit.
• Morning exercise isn't a magic bullet for burning more calories. Body temperature and hormones are higher in late afternoon and you may work out harder later in the day, matching the calorie-burning benefits of morning exercise.
Atkinson G, Reilly T. "Circadian variation in sports performance." Sports Med. 1996 Apr;21(4):292-312.
Shelley S. Tworoger, PhD1,2; Yutaka Yasui, PhD1; et. al. "Effects of a Yearlong Moderate-Intensity Exercise and a Stretching Intervention on Sleep Quality in Postmenopausal Women." SLEEP. 2003. Vol. 26, Issue 7, pages 830-836.