title: Does high-intensity resistance training maintain bone mass during moderate weight loss in older overweight adults with type 2 diabetes?
abstract: The aim was to investigate whether the addition of supervised high intensity progressive resistance training to a moderate weight loss program (RT+WLoss) could maintain bone mineral density (BMD) and lean mass compared to moderate weight loss (WLoss) alone in older overweight adults with type 2 diabetes. We also investigated whether any benefits derived from a supervised RT program could be sustained through an additional home-based program. This was a 12-month trial in which 36 sedentary, overweight adults aged 60 to 80 years with type 2 diabetes were randomized to either a supervised gymnasium-based RT+WLoss or WLoss program for 6 months (phase 1). Thereafter, all participants completed an additional 6-month home-based training without further dietary modification (phase 2). Total body and regional BMD and bone mineral content (BMC), fat mass (FM) and lean mass (LM) were assessed by DXA every 6 months. Diet, muscle strength (1-RM) and serum total testosterone, estradiol, SHBG, insulin and IGF-1 were measured every 3 months. No between group differences were detected for changes in any of the hormonal parameters at any measurement point. In phase 1, after 6 months of gymnasium-based training, weight and FM decreased similarly in both groups (P<0.01), but LM tended to increase in the RT+WLoss (n=16) relative to the WLoss (n=13) group [net difference (95% CI), 1.8% (0.2, 3.5), P<0.05]. Total body BMD and BMC remained unchanged in the RT+WLoss group, but decreased by 0.9 and 1.5%, respectively, in the WLoss group (interaction, P<0.05). Similar, though non-significant, changes were detected at the femoral neck and lumbar spine (L2-L4). In phase 2, after a further 6 months of home-based training, weight and FM increased significantly in both the RT+WLoss (n=14) and WLoss (n=12) group, but there were no significant changes in LM or total body or regional BMD or BMC in either group from 6 to 12 months. These results indicate that in older, overweight adults with type 2 diabetes, dietary modification should be combined with progressive resistance training to optimize the effects on body composition without having a negative effect on bone health.
authors.affiliation: Center for Physical Activity and Nutrition Research, School of Exercise and Nutrition Sciences, Deakin University, 221 Burwood Highway, Burwood, Melbourne, Australia. rmdaly@deakin.edu.au
authors.forename: Robin M
authors.initials: RM
authors.lastname: Daly
authors.forename: David W
authors.initials: DW
authors.lastname: Dunstan
authors.forename: Neville
authors.initials: N
authors.lastname: Owen
authors.forename: Damien
authors.initials: D
authors.lastname: Jolley
authors.forename: Jonathan E
authors.initials: JE
authors.lastname: Shaw
authors.forename: Paul Z
authors.initials: PZ
authors.lastname: Zimmet
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000032:analysis; D001823:Body Composition / Q000502:physiology; D015519:Bone Density / Q000502:physiology*; D001842:Bone and Bones / Q000503:physiopathology*; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000503:physiopathology*; D004032:Diet; D015444:Exercise / Q000502:physiology*; D005260:Female; D006699:Home Care Services; D006801:Humans; D008297:Male; D008875:Middle Aged; D009470:Muscle Spindles; D009765:Obesity / Q000150:complications / Q000503:physiopathology / Q000628:therapy*; D010349:Patient Compliance; D015431:Weight Loss / Q000502:physiology*
chemical_list: D015415:Biomarkers