It’s all in the Timing: Wall Street Journal reports time of day key to training success

How to Be Healthier, Happier and More Productive: It’s All in the Timing

Morning exercise may burn 20% more fat than later, post-food workouts.

The Wall Street Journal

Resolution: Get more exercise. It’s the most common New Year’s resolution. But when is the best time to hit the gym? Science has some answers, and most of them depend on the nature of our exercise goals.


Schedule exercise in the morning if you want to:

Lose weight. When we first wake up, having not eaten for at least eight hours, our blood sugar is low. Since we need blood sugar to fuel a run, morning exercise will use the fat stored in our tissues to supply the energy we need. (When we exercise after eating, we use the energy from the food we’ve just consumed.) In many cases, morning exercise may burn 20% more fat than later, post-food workouts.

Boost mood. Cardio workouts—swimming, running, even walking the dog—can elevate mood. When we exercise in the morning, we enjoy these effects all day. If you wait to exercise until the evening, you’ll end up sleeping through some of the good feelings.
Keep a routine. Some studies suggest that we’re more likely to adhere to our workout routine when we do it in the morning. So if you find yourself struggling to stick with a plan, morning exercise, especially if you enlist a regular partner, can help you form a habit.


Exercise in the late afternoon or evening if you want to:

Avoid injury. Studies have found that injuries are less common in workouts later in the day. Our body temperature reaches its high point in the late afternoon and early evening, and when our muscles are warm, they’re more elastic and less prone to injury.

Perform your best. In a 2015 study (01639-X) of 121 athletes, Elise Facer-Childs and Ronald Brandstaetter of the University of Birmingham found that individual performance can vary by as much as 26% based solely on time of day—and that performance typically peaks between 10 and 12 hours after awakening. So working out in the afternoons can help you sprint faster and lift more. Lung function is highest this time of the day, so your circulation system can distribute more oxygen and nutrients. This is also the time of day when strength peaks, reaction time quickens, hand-eye coordination sharpens, and heart rate and blood pressure drop. In fact, a disproportionate number of athletic records, especially in speed events, are set in the late afternoon and early evening.

Enjoy the workout a bit more. People typically perceive that they’re exerting themselves a little less in the afternoon even if they’re doing exactly the same exercise routine as in the morning, according to the American Council on Exercise.

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