The incidence of diabetes continues to rise alongside the incidence of obesity. In fact, according to the CDC, the incidence of diagnosed diabetes is now 8.2 per 1000 population which represents an increase of 148% over the past 28 years.
Given the comorbidity between obesity and diabetes, we’re now facing what’s been commonly referred to as the diabesity epidemic. For those who have body mass indexes (BMI’s) that are over 30 and fit in the category of obesity who also suffer from type 2 diabetes, the salient question is what they can do to reduce their risk of diabetic complications?
One of the primary complications of diabetes is the increased cardiovascular risk associated with diabetes. Most studies generally suggest that the cardiovascular risk is roughly twice as high in those who have diabetes. Diabetes is also the leading cause of kidney failure as well. Blindness in the form of diabetic retinopathy is also another serious complication of diabetes.
Common recommendations for those with diabetes includes adequate control of blood glucose levels, controlling blood pressure and cholesterol, eating a healthy balanced diet, regular exercise, not smoking, as well as regular visits to your dentist and optometrist.
For those who’re interested in maintaining a regular exercise routine, many wonder what type of exercise routine is most effective for helping them lose weight, abdominal fat, and to lower their HBA1C levels (a measure of glycosylated hemoglobin or long-term glycemic control).
Best exercise program for Diabetics?
A recent study published in the Journal of American Medical Association compared the effects of various training regimes on HBA1c levels, waist circumference, and weight loss in patients with type 2 diabetes .
Specifically, these researchers from Louisiana State University compared resistance training, cardiovascular training, and a combined routine to a nonexercise control group.
In total, 41 patients were randomized to the nonexercise control group while 73 participants were randomized to resistance training, 72 randomized to aerobic training, and 76 participants were randomized to combined aerobic and resistance training for a duration of 9 months each. The BMI’s of participants ranged from roughly 34-35 in all groups.
To ensure compliance, all exercise sessions were also supervised. On average, all exercise sessions amounted to a total of 150 minutes per week. For the aerobic group, their exercise sessions ranged between 50-80% of maximal oxygen consumption.
Participants who engaged in resistance training alone worked out 3 days per week. Each session included 2 sets of 4 upper body exercises (bench press, shoulder press, seated row, lat pull down), 3 sets of 3 leg exercises (leg press, extension, and flexion), and 2 sets of each of abdominal crunches and back extensions.
The combined resistance training and cardiovascular training group completed 2 resistance training sessions per week (1 set each of the previously mentioned 9 exercises) and one cardiovascular session per week.
- Compared with the control group, the absolute mean change in HbA(1c) in the combination training exercise group was -0.34% (95% confidence interval [CI], -0.64% to -0.03%; P = .03).
- The mean changes in HbA(1c) were not statistically significant in either the resistance training (-0.16%; 95% CI, -0.46% to 0.15%; P = .32) or the aerobic (-0.24%; 95% CI, -0.55% to 0.07%; P = .14) groups compared with the control group.
- Only the combination exercise group improved maximum oxygen consumption (mean, 1.0 mL/kg per min; 95% CI, 0.5-1.5, P < .05) compared with the control group.
- All exercise groups reduced waist circumference from -1.9 to -2.8 cm compared with the control group.
- The resistance training group lost a mean of -1.4 kg fat mass (95% CI, -2.0 to -0.7 kg; P < .05) and combination training group lost a mean of -1.7 (-2.3 to -1.1 kg; P < .05) compared with the control group.
The main finding of this study was that only the combined training program comprising both resistance training as well as cardiovascular training was effective for lowering HBA1C levels in patients with type 2 diabetes. The study authors noted that their observed reduction of -.3 to -.4% would equate to an expected 5-7% reduction of cardiovascular risk as well as a 12% reduction in the risk of microvascular complications (diabetic retinopathy, neuropathy, nephropathy).
The failure of the aerobic group to lose a substantial amount of weight (or fat) has been reported in numerous aerobic exercise trials, which may be due to aerobic training resulting in energy intake, expenditure compensation, or both.
One interesting finding in this study was that both the combined training and resistance training only groups lost fat mass while the aerobic only training group did not. For those interested in losing weight, this highlights the importance of including resistance training.