When is the best time of day to exercise to promote heart health? New research suggests that exercise at a specific time of day may be best for preventing heart disease and stroke. 

Study Summary 

This new research, which included 86,657 adults, found that: 

• Those who exercise in the morning (early morning = 8 am; late morning = 10 am) have the lowest risk for heart disease and stroke, when compared to those who exercise mid-day. 
• Those who are most active in the early morning have an 11% reduction in the risk for coronary artery disease, compared to those most active at mid-day. For women, this risk reduction was 22%.
• Those who are most active in the late morning have a 16% in the risk for coronary artery disease, compared to those most active at mid-day. For women, this risk reduction was 24%.

• There was a 17% reduction in the risk of stroke for participants who were most active in the later morning, when compared to those who were most active in mid-day. For women, this risk reduction was 35%. 
• After further analyzing these results based on sex, the findings are significant for women but not for men.

The Hearty Take

Since the study was observational, the researchers could not provide a reason as for why these associations were more prominent for women. However, the results suggest that in the future, time of exercise could be taken into consideration by professionals providing exercise recommendations, depending on long-term health and longevity goals of the patient. While the results suggest that late morning exercise may be the best exercise for preventing heart conditions, there is a need for more research.