Community Center–Based Resistance Training for the Maintenance of Glycemic Control in Adults With Type 2 Diabetes DAVID W. DUNSTAN, PHD 1 ELENA VULIKH, BSC 1 NEVILLE OWEN, PHD 2 DAMIEN JOLLEY, MSC 3 JONATHAN SHAW, MD 1 PAUL ZIMMET, PHD 1 OBJECTIVE — The purpose of this study was to determine whether beneficial effects on glycemic control of an initial laboratory-supervised resistance training program could be sus- tained through a community center– based maintenance program. RESEARCH DESIGN AND METHODS — We studied 57 overweight (BMI 27 kg/m 2 ) sedentary men and women aged 40 – 80 years with established (6 months) type 2 diabetes. Initially, all participants attended a twice-weekly 2-month supervised resistance training pro- gram conducted in the exercise laboratory. Thereafter, participants undertook a resistance train- ing maintenance program (2 times/week) for 12 months and were randomly assigned to carry this out either in a community fitness and recreation center (center) or in their domestic envi- ronment (home). Glycemic control (HbA 1c [A1C]) was assessed at 0, 2, and 14 months. RESULTS — Pooling data from the two groups for the 2-month supervised resistance training program showed that compared with baseline, mean A1C fell by -0.4% [95% CI -0.6 to -0.2]. Within-group comparisons showed that A1C remained lower than baseline values at 14 months in the center group (-0.4% [-0.7 to -0.03]) but not in the home group (-0.1% [-0.4 to 0.3]). However, no between-group differences were observed at each time point. Changes in A1C during the maintenance period were positively associated with exercise adherence in the center group only. CONCLUSIONS — Center-based but not home-based resistance training was associated with the maintenance of modestly improved glycemic control from baseline, which was propor- tional to program adherence. Our findings emphasize the need to develop and test behavioral methods to promote healthy lifestyles including increased physical activity in adults with type 2 diabetes. Diabetes Care 29:2586 –2591, 2006 C ontrolled trials have demonstrated that supervised resistance training may be a viable and effective exer- cise modality for the improvement of gly- cemic control in middle-aged and older adults with type 2 diabetes (1–3). These studies have typically elucidated the effi- cacy of resistance training using super- vised exercise sessions in well-controlled laboratory, clinic, or gymnasium settings. An advantage of this approach is that ex- ercise prescription can be carefully mon- itored to encourage both appropriate adherence and exercise progression to stimulate metabolic changes. However, from a public health perspective, the ef- fectiveness of maintenance programs un- dertaken in the community setting needs to be evaluated. Although maintenance programs undertaken in the home can provide convenience and flexibility (4), we have recently reported that home training for 6 months was not effective for maintaining the improvements in glyce- mic control associated with 6 months of supervised training in older persons with type 2 diabetes (5). The apparent ineffec- tiveness of home-based training was most likely due to reduced adherence and de- creased exercise training volume and intensity because the workloads experi- enced in the supervised setting could not be replicated with the hand and leg weights used in the home. Training programs in community facilities such as health and fitness cen- ters or gymnasiums offer greater access to resistance exercise equipment, super- vision, and group interaction than does home-based training. Such training at- tributes reflect several of the key social and environmental factors that can ben- eficially influence the maintenance of physical activity behaviors (6,7). How- ever, there is no evidence to date to de- termine whether such “center-based” resistance training in people with type 2 diabetes is effective for maintaining the improved glycemic control that has typ- ically followed laboratory-supervised resistance training interventions. In adults with type 2 diabetes who had completed an initial 2-month period of laboratory-supervised resistance training, we compared the outcomes of a community center– based long-term maintenance en- hancement intervention designed to max- imize environmental and social supports along with individual self-regulation with those of a control condition with reliance primarily upon individual self-regulatory capacities (home-based training). More specifically, we aimed to determine whether beneficial effects of the initial laboratory-supervised resistance training on glycemic control, body composition, and muscle strength could be sustained through the community center– based maintenance program. The associations of adherence to the resistance-training maintenance program with changes in glycemic control were also examined. ●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●● From the 1 International Diabetes Institute, Melbourne, Australia; the 2 Cancer Prevention Research Center, School of Population Health, The University of Queensland, Brisbane, Australia; and the 3 Monash Institute of Health Services Research, Melbourne, Australia. Address correspondence and reprint requests to Dr. David Dunstan, International Diabetes Institute, 250 Kooyong Rd., Caulfield, Victoria, Australia 3162. E-mail: ddunstan@idi.org.au. Received for publication 22 June 2006 and accepted in revised form 26 August 2006. Abbreviations: HOMA, homeostasis model assessment; LBM, lean body mass; 1-RM, one-repetition maximum strength. A table elsewhere in this issue shows conventional and Syste `me International (SI) units and conversion factors for many substances. DOI: 10.2337/dc06-1310. Clinical trial reg. no. ACTRN012605000336684, clinicaltrials.gov. © 2006 by the American Diabetes Association. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact. Clinical Care/Education/Nutrition O R I G I N A L A R T I C L E 2586 DIABETES CARE, VOLUME 29, NUMBER 12, DECEMBER 2006