High intensity exercise gives beta cells new strength, study finds

A small pilot study has found that six weeks of a high intensity training called CrossFit helped people with type 2 diabetes regain beta cell function and reduce their body fat.
Researchers at the Case Western Reserve University had 12 adults with type 2 diabetes do 10 to 20 minutes of CrossFit at a gym three days per week for six weeks.
Their workout consisted in completing several rounds of a wide variety of functional exercises, such as pull-ups, squats and push-ups, with each rep performed explosively.
The participants were all considered sedentary prior to starting the program. None of them were insulin-treated, but some were receiving metformin.
After six weeks of CrossFit, researchers assessed body composition via a DEXA scan and found a mean reduction of 1.1% in total body fat percentage and a mean weight loss of 1.8 kg. Lean body mass (LBM) was preserved.
Researchers used what’s known as the fasting proinsulin to insulin ratio as a way to gauge beta cell function and compared the value obtained pre- and post-CrossFit.
An elevated proinsulin to insulin ratio is a marker for beta cell dysfunction and is indicative of a progressive deterioration of insulin secretion within the beta cells.
After six weeks of CrossFit, researchers found that the proinsulin to insulin ratio was significantly reduced, which means that beta-cells’ secretory capacity had improved.
Another index of improved beta cell function that was looked at is the Disposition Index (DI), which increased compared to baseline levels in some of the participants.
Few studies have reported on the health effects of high intensity exercise, and this is the first such study concerning beta cell function in type 2 diabetes.
Any physical activity can positively impact insulin sensitivity, but high intensity training may be the exercise modality that has the most profound effect on beta cells.
The findings, published in the American Journal of Physiology, Endocrinology and Metabolism, suggest that an one hour of CrossFit like training per week may greatly benefit people with type 2 diabetes.