Working out does improve your metabolism, but there is no advantage to exercising before bed. In fact, hitting the gym too late can interfere with sleep, which itself is an important component of weight loss. Rather than worrying about the time of your workout, focus on maintaining a regular exercise routine. Work out when you feel the most energized and are least likely to experience negative side effects from exercise.
Working Out at Night
If you function at your peak before bed and exercise doesn't disrupt your sleep patterns, then night is as good a time as any to work out. However, there is no added metabolism boost, and heavy physical activity may prevent you from falling asleep if you do it within three hours of bedtime. According to Phyllis Zee, M.D., a circadian biology professor at Northwestern University, the ideal time for exercise is between 2 to 6 p.m. That's when you have the greatest lung function and tolerance for physical discomfort.
Cardio and Metabolism
Performing aerobic activities like running, biking, skiing and swimming elevate your metabolism while you are performing them and for hours after you've finished. While time of day does not affect this boost, the intensity of your cardio workout does. For maximum benefit, add interval training to your routine. Push yourself hard for a short time, go back to a more leisurely pace, and then repeat to torch away calories faster. For example, you might run or jog for two minutes and then walk for two minutes, repeating the cycle for 40 minutes.
Strength Training and Metabolism
Strength training builds up your muscles; the more muscle tissue you have, the more calories you burn throughout the day. This is because it takes six calories a day just to maintain muscles at rest. In comparison, it only takes two calories a day to maintain fat. Lifting weights, doing squats and performing crunches are all considered strength training exercises. Keep in mind that the metabolism boost will not be instant, as it takes time to build up enough muscle to make a real difference.
Exercise and Insomnia
Overall, exercise will help your sleep, allowing you to drift off more quickly and rest throughout the night. However, working out before bed can lead to insomnia. This is because exercise triggers your body to produce a hormone called cortisol, which keeps you alert. This alertness is beneficial in the daytime, but can prevent you from dozing off when you need to. To avoid sleeplessness, the Division of Sleep Medicine at Harvard Medical School recommends working out at least two to three hours before you turn in for the night.
- University of Rochester Medical Center: Set Your Clock to Workout Time
- WebMD: Slideshow: 10 Ways to Boost Your Metabolism, Page 3
- Mayoclinic.com: Rev Up Your Workout with Interval Training
- WebMD: Slideshow: 10 Ways to Boost Your Metabolism, Page 2
- Harvard Medical School: Twelve Simple Tips to Improve Your Sleep
Nina K. is a Los Angeles-based journalist who has been published by USAToday.com, Fitday.com, Healthy Living Magazine, Organic Authority and numerous other print and web publications. She has a philosophy degree from the University of Colorado and a journalism certificate from UCLA.
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