Evening exercise most effective in lowering blood sugar levels: Study

New research, published in the journal Obesity, revealed that moderate to vigorous physical activity in the evening for sedentary adults with overweight and obesity is most beneficial in lowering daily blood sugar levels.

Experts explain that it has been well established that moderate to vigorous physical activity enhances glucose homeostasis in adults with overweight and obesity who are at higher risk of developing insulin resistance.

Exercise helps lower blood sugar levels by increasing insulin sensitivity and facilitating glucose uptake by muscles. During physical activity, muscles use glucose as an energy source, reducing the amount of glucose in the bloodstream. This effect continues even after exercising, as the muscles continue to replenish their glycogen stores, further lowering blood sugar levels. Regular exercise also helps maintain a healthy weight and improves overall metabolic health, which is crucial for effective blood sugar management, especially in overweight and obese individuals.

In the study, 186 adults with an average age of 46 years and a body mass index of 32.9 kg/m² participated in a cross-sectional analysis. Researchers monitored the participants' physical activity and glucose patterns over 14 days with a continuous glucose-monitoring device.

The volume of moderate to vigorous physical activity accumulated each day was classified: as inactive (no activity accumulated), 'morning' (more than 50% of activity between 6 a.m. to noon), 'afternoon' (more than 50% of activity between noon to 6 p.m.), 'evening' (more than 50% of activity between 6 p.m. to midnight), or 'mixed' (no single time window accounted for greater than 50% of the activity).

The results showed that accumulating greater than 50% of moderate to vigorous physical activity in the evening was associated with lowering day, night, and overall blood glucose levels compared with being inactive. This association was stronger in those participants with impaired glucose regulation. The pattern of these associations was similar in both men and women.

“Our results highlight the importance of the field of precision exercise prescription. In clinical practice, certified sports and medical personnel should consider the optimal timing of the day to enhance the effectiveness of the exercise and physical activity programs they prescribe,” said Jonatan R. Ruiz, professor of physical activity and health, at the University of Granada.

Reference: Clavero-Jimeno, A., et al. (2024) Impact of lifestyle moderate-to-vigorous physical activity timing on glycemic control in sedentary adults with overweight/obesity and metabolic impairments. Obesity. doi.org/10.1002/oby.24063.