A new study investigates the potential effect of exercising at different times for preventing cardiovascular disease and stroke.

The study finds that people who exercise in the morning achieve the greatest reduction in risk. This is particularly true for women. According to the study, the best time of day to exercise may be around 11 a.m.

Although exercise is always generally good for health, a large new prospective study finds that one particular time of day may offer the greatest benefit when it comes to lowering the risk of cardiovascular disease (CVD) and stroke.

The study found that physical activity in the morning, between 8 and 11 a.m., had the greatest positive effect on a person’s risk of CVD and stroke compared to activity at other times of day.

The association applied equally to individuals who described themselves as morning or evening people.

The study authors also found that people who exercised both early and late in the morning — versus mid-morning — derived the greatest benefit.

Dr. Paul Arciero, professor in the Human Physiological Sciences Department at Skidmore College in Sarasota Springs, NY, explained why the study is so persuasive:

“This is the largest prospective study to date in more than 86,000 participants, over a six-year follow-up period, examining the effects of exercise time of day, or ‘chronoactivity,’ on cardiovascular disease [heart attack and stroke] risk.”

Dr. Asad R. Siddiqi commented:

“I think this study does a great job of trying to tackle a few of the biggest challenges in physical activity intervention research. Namely, [the] scale of study, generalizability, and follow-up interval.”

Dr. Siddiqi is an assistant professor of clinical rehabilitation medicine at Columbia University Medical Center, NY. Neither he nor Dr. Arciero were involved in the study.

The study appears in the European Journal of Preventive Cardiology.