Intermittent, intense exercise benefits heart abnormalities in people with type 2 diabetes

by Bruce Sylvester: High intensity intermittent exercise improves both heart structure and glucose control in patients with type 2 diabetes, researchers reported on Sept. 9, 2015 in Diabetologia.

“This study demonstrates, for the first time, that exercise can begin to reverse some of the early cardiac changes that are commonly found in people with type 2 diabetes. Interestingly, the data also suggest that this type of high intensity intermittent exercise benefits both the heart and diabetes control, but the benefits appear to be greatest in the heart,” the authors wrote. “The strong positive effect of exercise on the heart is, although completely logical, a message that needs to be communicated to people with type 2 diabetes more clearly,” they added.

The research was led by Professor Michael Trenell and Dr. Sophie Cassidy from Newcastle University (UK). It is the first research to demonstrate that such exercise training improves heart structure and benefits diabetes control.

As background, the authors noted that persons with type 2 diabetes have a doubled risk of heart disease compared to non-diabetics. Also diabetes causes changes early in the course of the disease, with changes in the structure and function of the left ventricle appearing before any subsequently emerging symptoms of heart disease.

The researchers used this study to test effects of repeated, brief short (up to 90 seconds) intense cycling, also called high intensity intermittent exercise, on diabetes control and on the heart.

The study included 23 type 2 diabetes patients, aged 45 to 71. Twelve subjects were randomized to 12 weeks of intermittent high-intensity exercise, and 11 continued standard treatment.

The investigators evaluated changes in heart structure and function with advanced magnetic resonance imaging. They evaluated diabetes control with a standard oral glucose tolerance test.

They reported that high intensity intermittent exercise significantly improved cardiac structure and function, notably in the left ventricle. They also found a significant improvement in diabetes control.

They concluded, “The data reinforce how important a physically active lifestyle is for people with type 2 diabetes. Our findings also suggest that exercise does not have to be 30 minutes of continuous exercise – repeated short bouts of higher intensity exercise give strong benefits to the heart. Getting more physically active is, quite literally, at the heart of good diabetes control.”

The research funded by the National Institute for Health Research (UK).