Ask the Experts: Ben Greenfield on Training and Time of Day
Tuesday, August 26, 2008 at 10:24AM Question: Should I exercise in the morning or the evening?
Answer: Depends on your goals! If you are exercising for sports performance and want to be able to achieve the highest possible intensities during your routine, then the optimal time to exercise is when your body temperature is at its highest. For most people, this is about 4p to 5p in the afternoon. On the other hand, your body temperature is at its lowest just before you wake, so rolling out of bed for an interval training session may not be the best idea. In addition, research has shown that your aerobic capacity, strength output, and sprint capabilities are also higher in the afternoon (but only by 4-5%).
Conversely, morning exercise does have benefits. By jump-starting your metabolism and increasing your core temperature early in the day, you increase your post-exercise oxygen deficit and calorie-burning rate throughout the remainder of the day. Therefore, if you are trying to lose weight or burn fat, a morning exercise session can be highly effective. Psychologically, you may be more likely to exercise in the morning, versus after a hard day of work, when your mind and body may be tired or you may have too many other duties to fulfill. It doesnt matter if youre able to exercise with higher intensity in the afternoon if you never actually get around to doing it!
The ultimate combination, and the system I implement for my clients who want to simultaneously build fitness and burn fat, is an aerobic morning exercise session of 30-60 minutes, followed by a more intense interval, sport-specific, or resistance training session in the late afternoon or evening.
About the author:
Ben Greenfield is recognized as one of the top fitness, triathlon, nutrition and metabolism experts in the nation. In 2008, he was voted as the Personal Trainer of the Year by the National Strength and Conditioning Association, an internationally recognized and respected certifying agency. Ben is Director of Sports Performance and oversees the physiology and biomechanics laboratory at Champions Sports Medicine in Spokane, WA, which offers metabolic-based weight loss, bicycle fitting, running gait analysis, swim stroke analysis, VO2 max testing, blood lactate testing, resting metabolic rate analysis, and other cutting-edge procedures for weight loss and performance.
Ben hosts the highly popular fitness, nutrition and wellness website at www.bengreenfieldfitness.com, which features blogs, podcasts, and product reviews from Ben. In addition to coaching and training for weight loss and sports performance, Ben serves as a business and marketing consultant to fitness professionals, and is the host of a weekly syndicated fitness business blog and podcast at http://www.trainfortopdollar.com. E-mail: ben@bengreenfieldfitness.com
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Reader Comments (2)
This is what I've observed in my own body, in years of triathlon training - that the ideal combination is aerobic endurance in the morning, and specific, higher-intensity sessions in the evening. I keep thinking I should set up an early-evening triathlon! The intensity:body temperature correlation totally makes sense to me; getting up for a 7:00 AM track workout never did.
Thanks for the clarification.
Diana
weight loss fitness...
Good post. You’ve just confirmed what I’ve been thinking about this....