A woman looking at a city in the distance.Share on Pinterest
New research suggests that exercising in the afternoon may have the most benefits for people living with type 2 diabetes. Azman Jaka/Getty Images
  • Exercise can provide several benefits for those with diabetes, including lowering blood sugar.
  • Better blood sugar control may reduce your risk for heart disease and other adverse effects.
  • New research indicates that afternoon exercise in particular seems to help blood sugar control.
  • However, it is not yet certain why afternoon exercise would be more beneficial.
  • Experts say they generally advise regular exercise as a part of diabetes management.

The American Diabetes Association notes that, as of 2019, 37.3 million Americans (11.3% of the population) are living with diabetes.

Diabetes, per the Centers for Disease Control and Prevention (CDC), is a medical condition in which your body either doesn’t make enough of the hormone insulin (type 1 diabetes) or it can’t use it as well as it should (type 2 diabetes). Insulin plays a vital role in removing sugar from your blood and getting it into your cells where it can be used for energy.

If you are living with this condition, the CDC advises that one way you can manage your symptoms is by getting more exercise.

Physical activity helps increase your sensitivity to insulin and lowers blood sugar. This, in turn, can help reduce your risk for associated nerve damage and heart disease.

Now, scientists at Brigham and Women’s Hospital and Joslin Diabetes Center have published new research in the journal Diabetes Care indicating that people with type 2 diabetes might see the most improvements in blood sugar control if they exercise in the afternoon rather than the morning or evening.

The study utilized data from the Look AHEAD (Action for Health in Diabetes) study.

This study was a randomized controlled trial comparing how an intensive lifestyle intervention, along with support and education, might help prevent cardiovascular disease for type 2 diabetes patients who are also living with obesity or overweight.

For the current study, the researchers looked at how exercise at particular times of the day influenced blood sugar control.

Altogether, they included 2,400 people, examining data from the first and fourth years of the Look AHEAD study.

To determine the participants’ level of physical activity, each person wore a waist accelerometry recording device.

Upon review of the data, the team discovered that in the first year, people who had moderate-to-vigorous levels of activity in the afternoon has the largest reduction in blood sugar levels.

This same group maintained the observed reduction in blood sugar levels in the fourth year.

Further, those who were most active in the afternoon were most likely to have been able to stop taking their diabetes medications because of these improvements in blood sugar control.

Dr. Jingyi Qian, from the Division of Sleep and Circadian Disorders at Massachusetts’ Brigham and Women’s Hospital, and co-corresponding author Dr. Roeland Middelbeek, assistant investigator at Joslin Diabetes Center, told Healthline it is not yet clear why afternoon exercise might be better for type 2 diabetes.

However, one common hypothesis is that the circadian system might play a role.

“This circadian system regulates many physiological functions in our body, which may play a role in the time-specific benefits of physical activity,” said Qian and Middlebeek.

Another speculation is that behavioral factors — such as fasting/postprandial states or sleep-wake cycles — could contribute to the observed benefits.

“For example, post-meal physical activity, which may be occurring most often after lunch in the afternoon group, is an effective strategy for managing postprandial glucose excursions in type 2 diabetes,” the pair noted.

While particular benefits were seen with afternoon exercise, the authors note that exercise any time of the day is helpful for people with type 2 diabetes.

Not only can it improve blood sugar readings; but, to some extent, it can also help manage weight, they say.

Dr. Kathleen Dungan, Professor of Medicine and Interim Director of the Division of Endocrinology, Diabetes & Metabolism at The Ohio State University, agrees, calling exercise “vitally important” for people with diabetes.

“Exercise can rapidly lower the glucose level … by driving excess glucose into the skeletal muscle,” she explained, “Moreover the immediate effects of exercise can linger for many hours after completion of the activity.”

Dungan said that exercise is also linked to lower blood pressure and more favorable cholesterol levels, which may reduce your risk for cardiovascular events or death.

And, as an added bonus, it can help improve your mood and your sense of well-being.

Amanda Beaver, MS, RDN, LD, Wellness Dietitian at Houston Methodist Wellness Services, said that how much exercise you need will depend on the intensity of the exercise. But, for most people living with diabetes, she said it’s recommended to get 150 minutes or more of moderate-to-vigorous exercise per week.

“In the fitness world, moderate-intensity exercise is when we can talk, but not sing (try it for yourself next time you exercise),” she suggested.

She added that other great examples of moderate-intensity exercise include:

“It is not recommended to go more than two days in a row without exercise as it can increase insulin resistance,” said Beaver. “This means exercise should be spread out over at least 3 days of the week.”

Beaver added that one type of exercise that is often overlooked is resistance training, which is recommended to be done 2-3 times per week.

“This does not necessarily have to be lifting weights in a gym,” she said, “even barre and Pilates work well for this.”

Finally, Beaver advised that people with type 2 diabetes should keep an eye on how much time they spend sitting.

“It is recommended to stand up about every 30 minutes as some studies have shown this can improve blood sugar control,” she concluded