The Long-Term Effects of Resistance Training and Diet in Elderly Type 2 Diabetics

This study is a two-arm, 12-month RCT which will consist of two phases involving older overweight and obese adults with type 2 diabetes. Specifically, the program is designed to investigate whether 6 months of high intensity progressive resistance training (PRT) within a supervised and structured setting combined with weight loss (WL) can reduce HbA1C, increase muscle strength and lean body mass and decrease fat mass in older overweight and obese adults with T2D compared to weight loss alone Following baseline assessments, participants will be randomised (1:1) ratio to receive either PRT + WL or sham (flexibility) training + WL. An accredited Exercise Physiologist will prescribe and supervise the initial exercise program. Those participants allocated to PRT + WL for the first six-months will attend the exercise laboratory at Deakin University three non-consecutive days per week and perform an individually prescribed 45-60 minutes, high intensity (75-85% of their one repetition maximum strength) program consisting of free weights and weights machines (three sets of 8-10 repetitions, nine exercises). Following the 6-month supervised gym-based intervention, participants will be prescribed a home-based exercise program in which they will be provided with individual instructions and equipment (dumbbells and ankle weights). Participants will be asked to train three days per week at home and/or at a community or commercial leisure centre. To facilitate transition to the home-based intervention, participants in the PRT + WL group will perform the home-based PRT program within the structured and supervised gym setting for the final month of phase 1. The home-based exercises (duration: 45-60 minutes) will replace weights machines with dumbbells and ankle weights and participants will be requested to complete nine exercises (three sets of 8-10 repetitions) with aim to exercise at a moderate intensity (at least 60% of maximum). Participants will attend the gymnasium once per month to monitor technique and progression and complete weekly exercise diaries to monitor adherence. In addition, weekly phone calls (first month) and subsequent fortnightly calls will monitor adherence and enable participant questions and feedback. Home visits will be conducted in week one to ensure safety and provide additional weights to facilitate progression. All participants will also be placed on a healthy eating plan supplying less than or equal to 30% total energy from total fat (less than or equal to 10% saturated fat) with protein and carbohydrate being distributed for remaining energy. Individually prescribed by a dietitian, the healthy eating plan is designed to induce moderate weight loss (~0.25 kg per week) throughout phase 1. Interviews every two weeks by the dietitian and completion of a weekly checklist will be used to assess adherence. Changes in nutrient intake will be assessed via a 3-day food record conducted at 3 and 6 months. Nutrition information will be analysed using Foodworks nutrient analysis software (Xyris, Brisbane, Queensland, Australia). Following the first 6-month gym-based intervention, participants will not be required to adhere to the healthy eating (WL) plan and will not receive further dietary recommendations.