What Time Should You Exercise to Burn Fat?

Reaching an ideal weight is an important goal for people who want to live healthily. Ideal weight is calculated using body mass index (BMI). An adult with a body mass index between 20 and 25 is considered to be at an ideal weight. Being obese increases the risk of many diseases, particularly cancer. We should incorporate exercise into our daily lives to maintain or reach an ideal weight (see which cancers does exercise reduce the risk of?).

It is important to choose a suitable time for exercise and stick to it. Many people who want to exercise regularly are unsure when to fit it into their daily lives. Exercising at the right time, however, may further increase its benefits.

What Time Should You Exercise?

In July 2019, Cell published an article on the relationship between the biological clock and metabolism. In the study, experiments conducted first in mice and then in humans showed that exercising in the evening might be more effective.

Studies found that our oxygen consumption is lower in the evening, giving us higher performance. They also found that the HIF1alpha protein was activated more by evening exercise. HIF1α protein increases carbohydrate breakdown during exercise, directing the body toward alternative energy sources such as fat. High-performance evening exercise may therefore help us lose weight faster (reference 1).

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The findings also appear consistent with recommendations from the American Council on Exercise. The Council supports the result, stating, “muscles that warm up during the day perform better in the evening”. It also says that blood pressure is better controlled during evening exercise (2).

When exercising in the evening, eat appropriately before exercise and do not exercise close to bedtime. Although other evidence supports evening exercise as better for weight loss, it should be noted that this evidence is limited.

Despite the recommendation for evening exercise, there may be situations in which you prefer exercising in the morning. If you want to start the day with exercise, doing so before breakfast is recommended. Because fat burning is faster after the overnight fast, exercising at this time may be better for you (3). However, you need to watch for low fasting blood sugar, called hypoglycemia. It is therefore recommended that you follow advice tailored to you by your physician and dietitian.

More research is needed to reach a clear conclusion about the right exercise time. Whether you exercise in the evening or morning, exercising correctly and regularly matters more for healthy living. Supporting it with sufficient sleep and a balanced diet can also help you get more from exercise and reach your goal more easily.