Frequent exercise breaks during prolonged sitting may be better for blood vessel health in people with type 2 diabetes than less-frequent activity interruptions. The first-of-its-kind study is published ahead of print in the American Journal of Physiology-Heart and Circulatory Physiology.

People living with type 2 diabetes have a higher risk of heart disease and reduced vascular (blood vessel) function than those without the metabolic disorder. Measuring vascular function is often used to determine the risk of cardiovascular disease. Increasing physical activity and decreasing the amount of time sitting—in all populations, not just those with diabetes—has been shown in previous studies to reduce the risk of heart disease. However, with “rapidly advancing technologies in workplaces, transportation and home entertainment, fewer opportunities exist for incidental activity, creating many contexts of daily life that are conducive to prolonged sitting,” authors of a new study wrote.

Researchers of the new study explored the effects of shorter, more frequent and longer, less-frequent exercise breaks on blood flow and blood vessel dilation in adults with obesity and type 2 diabetes. Each volunteer participated in three separate trial conditions on different days. In one condition, the volunteers sat for eight hours, during which time they could read or use a phone, but they did not take activity breaks. In a second condition, the volunteers performed three minutes of exercises that included squats, leg lifts and calf raises every 30 minutes. The third condition consisted of six-minute exercise breaks every hour. The research team measured the participants’ glucose and insulin levels, blood pressure and blood flow throughout each trial condition.

Compared with sitting, blood vessel function tended to improve throughout the day in both exercise conditions, but with significantly more beneficial results when the participants exercised every 30 minutes, suggesting that the frequency of the activity break may be more important than the length of time. “Given that there is a progressive impairment in vascular function throughout the pathogenesis of type 2 diabetes, it is possible that more frequent interruptions to sitting are needed to preserve leg blood flow,” the researchers wrote.

“Our findings suggest that more-frequent and shorter breaks may be more beneficial than longer, less-frequent breaks for improvement in vascular function in those with type 2 diabetes,” the researchers wrote.

Read the full article, “Acute effects of interrupting prolonged sitting on vascular function in type 2 diabetes,” published ahead of print in the American Journal of Physiology-Heart and Circulatory Physiology.