STRONG-D: Strength training regimen for normal weight diabetics: Rationale and design.

Background: Currently, there is a lack of data on effective lifestyle recommendations for normal-weight diabetics (NWD), who can represent up to 1 in 5 individuals with Type II Diabetes Mellitus (T2DM). NWD is especially prevalent in Asian populations and the elderly. Specific exercise treatment recommendations are needed for patients with normal-weight diabetes (NWD), as those in this category face higher mortality rates than overweight and obese diabetics. Standard T2DM treatment recommends aerobic training; however, performing aerobic training alone may not be appropriate for NWD and strength training may be a more effective treatment recommendation.

Objective: While it is known that strength and aerobic training are beneficial in obese diabetics, there is currently insufficient evidence to recommend this regimen in NWD. The Strength Training Regimen for Normal Weight Diabetics (STRONG-D) study aims to determine the best exercise regimen for NWD and address the current lack of appropriate physical activity recommendations for this population. The primary goal of this study is to determine whether strength training aids glycemic control better than aerobic training in NWD.

Study Design: STRONG-D is a three-arm randomized controlled trial designed to compare the clinical effectiveness of structured strength training only, aerobic training only, and combination (strength + aerobic) training sessions, modeled after the intervention in the Health Benefits of Aerobic and Resistance Training in T2DM patients (HART-D) study. Potential participants meeting eligibility criteria of HbA1c values of 6.5% to 13.0% and BMI of 18.5 kg/m to 25 kg/m will be enrolled. After randomization, participants will begin a 9-month exercise intervention. The primary outcomes will be HbA1c levels. The secondary endpoints will include physical fitness, body composition measured by Dual X-Ray Absorptiometry (DXA) scans, and leg strength and endurance measured by Biodex testing. Initial follow-up visits will occur at 3 months, 6 months, and 9 months. To determine the long-term effects of the exercise intervention, passive follow-up will continue via electronic health records (EHR) until a 24-month follow-up visit. A total of 282 participants will be randomized into the three study arms determine the clinically significant differences between strength-only, aerobic-only and combination regimens.