Exercise as it relates to Disease/The Effect of High Intensity Resistance Training on Glycemic Control in Older Type 2 Diabetics

Title - The Effect of High Intensity Resistance Training on Glycemic Control in Older Type 2 Diabetics

(Dunstan DW, Daly RM, Owen N, Damien J, Courten M, Shaw J, Zimmet P. High-Intensity Resistance Training Improves Glycemic Control in Older Patients with Type 2 Diabetes. DiabCare. 2002 October; 25 (10): 1729-1736)

Research Background

 * Type II Diabetes - Type II Diabetes is a lifestyle disease in which the pancrease gradually loses the ability to produce enough insulin. According to Diabetes Australia and Better Health Victoria, type II diabetes can be caused by lifestyle and genetic factors including: older age, being overweight/obesity, high blood pressure, cardiovascular disease, little or no physical activity and smoking.
 * Glycemic Control - Glycemic control is maintaining blood glucose levels within a range of 6-8 mmol/L (for type 2 diabetics) to help treat and regulate diabetics mellitus. Glycemic control can be controlled through a variety of methods, some include: continuous home monitoring of glucose, Exenatide (Exendin-4), and resistance training.
 * High Intensity Resistance Training - According to Better Health Victoria, resistance training (also known as strength or weight training) uses resistance to build strength throughout muscular contraction. High Intensity resistance training involves more weight and a higher intensity of sets of reps.

Research Information

 * Where is the research from? - This study was held in Victoria, Australia and conducted by researches from the International Diabetes Institute, School of Health Sciences - Deakin University and School of Population Health - University of Queensland. This study was published in Diabetes Care Journal in 2002.
 * What kind of research was this? - This study was a clinical controlled trial to assess whether high-intensity resistance training has an effect in improving glycemic control in older type II diabetics.
 * What did the research involve? - This study investigated the effects of high-intensity resistance training (HIRT) on glycemic control in older type II diabetes. 29 overweight men and women aged 60–80yrs were randomly split into two groups:
 * High-Intensity Progressive Resistance Training + Moderate Weight-Loss [RT & WL]
 * Moderate Weight-Loss + Control Program [WL]



Each participant attended 3 exercise sessions per week for 6 months in a laboratory setting under supervision.

RT & WL group goal was to achieve 75-80% of their 1RM with a program consisting of 5min warm-up, 45min HIRT and 5min cool-down. Various exercises were used including: bench press, leg extension, dumbbell seated shoulder press, bicep curl and abdominal curls. The workload for each exercise was regularly increased to achieve 3 sets of 10 reps. 1RM was tested every 12 weeks to set a new baseline measure.

The WL group goal was the achieve weight loss. There program consisted of 5min stationary cycling and 30min static stretching.

Both groups also undertook a healthy eating plan for the first 4 weeks designed to cause 0.25 kg weight loss per week. After 4 weeks, participants met with a dietitian to complete a weekly food checklist. 3 day food records were taken at 3 and 6 months to compare nutrients changes across the trial.


 * Pre & Post Testing Procedures - Pre and Post testing procedures included: anthropometry, muscle strength (using 1RM), habitual physical activity, resting blood pressures and a blood sample to measure different blood markers.

Results

 * Interpreting Results - The researchers concluded that a high-intensity resistance training program has a positive effect in improving glycemic control in older type II diabetics. Participants also achieved a reduction in fat mass making the training program a valid source of research therefore opening more areas for further investigation/research.
 * Implications of Research- The implications of this research along with previous studies suggest that high intensity resistance training has a positive effect in improving glycemic control in older type II diabetics and moderate weight loss.
 * Further Research - Type II diabetes is currently responsible for 85% of diabetes in Australia, therefore this study suggests further research options for improving glycemic control in older type II diabetics utilizing high intensity resistance training: training periods longer than 6 months, sessions held outside a lab-based setting and identifying the optimal intensity of resistance training to safety train and gain maximal effects.

Conclusions
This study investigated the effects on glycemic control in older type II diabetics throughout a high-intensity resistance training program. Results demonstrated that the program was effective. The RT & WL group showed a 0.8% decrease in HBLA1c therefore improving glycemic control. Both groups experienced a reduction in body weight and fat mass. Alongside supporting evidence, this study shows glycemic control in older type II diabetics can be controlled with a high-intensity resistance training program and a moderate weight loss.