Pair of Exercise Studies Show Different Ways to Take on Diabetes

This year’s theme of promoting healthier lifestyles continued at Tuesday’s poster session at the American Heart Association Scientific Sessions, with researchers presenting different approaches to exercise for patients with type 2 diabetes (T2D).

Bursts of exercise. Short periods of intense exercise may be best for those with newly diagnosed T2D, according to a study whose lead author is an undergraduate student at the University of Western Ontario in London, Ontario.

Cholesterol levels, blood sugar, and weight improved greatly among T2D patients who had 10 minutes of high-intensity exercise 3 times a day, 5 days a week, compared with a group who exercised on a more traditional schedule of 30 minutes at a lower intensity, also for 5 days a week. The study involved 76 patients, 70% male, who were recruited shortly after being diagnosed with T2D.

Burst exercise patients actually ended up getting more activity overall, and had 2.3 times greater improvement in glycated hemoglobin levels and 3 times the reduction in their body mass index (BMI) than their counterparts in the traditional exercise program. The burst patients outperformed the traditional patients on stressed tests and did better on cholesterol screenings.

The study’s lead author, Avinash Pandey, speculated that it may be easier to fit the short periods of exercise into busy schedules. “People randomized to that regimen were more consistent with exercise and ended up doing more exercise per week,” he said in a statement. In his abstract, Pandey said the level was actually 27% more.¹

Yale study. The National Institutes of Health (NIH) paid for a study that looked for ways to get rid of the high amounts of visceral fat that come with insulin resistance, which can lead to T2D as well as cardiovascular disease. A team from Yale University led by Soohyn Nam randomized 77 participants ages 35 to 65 years of age who had T2D or prediabetes, to either a diet for 6 months or a diet combined with supervised moderate intensity exercise training. In the group, 37 already had T2D and 40 had prediabetes.

Outcomes in the study were visceral and subcutaneous fat volumes, which were measured through magnetic resonance imaging (MRI); aerobic fitness, as measured by VO₂ peak during a treadmill test, body mass index (BMI), and glycated hemoglobin levels (A1C).

Of the 77 subjects (mean age 54.8 years, mean BMI 34.5), there was substantial average weight loss in both groups, but wide variation within each group, and this showed up in the similarity in all the measures between the diet only and diet exercise groups. The 2 groups did not differ substantially in their changes for body weight: the diet group had lost 6.04 kg while the diet and exercise group had lost an average of 6.68 kg. For abdominal fat, results were also about the same: the diet only group lost 101.93 cm² and the diet and exercise group was a fraction lower at 104.15 cm². In visceral fat reductions, the diet only group did slightly better but not much, -25.53 cm² vs -23.24 cm². Measures of A1C were also nearly identical.²

What the study showed, the researchers said, was that when patients with T2D or prediabetes can manage to lose belly fat, they will see improved A1C. The trouble is, not all do.

References

1. Pandey A. Poirer P. The impacts of burst exercise compared to sustained exercise on the cardiometabolic status and exercise behavior of newly diagnosed type 2 diabetic patients. Presented at the American Heart Association Scientific Sessions; Orlando, Florida, November 10, 2015; poster T-2088.

2. Nam S, Dobrosielski DA, Stewart KJ et al. Effect of a lifestyle weight loss intervention on visceral fat and glycemic control among individuals with and without type 2 diabetes. Presented at the American Heart Association Scientific Sessions; Orlando, Florida; November 10, 2015; poster T-2091.