Article

Regional muscle glucose uptake remains elevated one week after cessation of resistance training independent of altered insulin sensitivity response in older adults with Type 2 diabetes

University of Utah Department of Physical Therapy, Salt Lake City, Utah, United States of America.
Journal of endocrinological investigation (Impact Factor: 1.65). 04/2012; 36(2). DOI: 10.3275/8333
Source: PubMed

ABSTRACT Background: Aging is associated with a decline in skeletal muscle size. Muscle is critical both for mobility and glucose disposal. While resistance exercise (RE) increases muscle mass and function in the elderly, its role in improving glucose utilization is less clear. Aims: To investigate whether muscle size was linked with insulin sensitivity (IS) in elders with diabetes following RE and if regional muscle glucose uptake differed from systemic glucose utilization. Method: Seven (68.4±5.9 yrs) adults with diabetes participated. After 16 weeks of RE, within 24 hours (post 1) and after 1 week of no exercise (post 2), lean tissue cross-sectional area (CSA) and IS via glucose infusion rate (GIR) were assessed along with a standardized FDG-PET uptake value (SUV). Results: CSA increased between pretest (108.5±35.3 cm2) and post 1 (116.8±40.9 cm2), p=0.02 and did not differ at post 2 (116.0±39.3 cm2). GIR during the 40 mU/m2/min insulin clamp differed between pretest (22.0±15.8 mg/kg/min) and post 1 (67.9±72.8 mg/kg/min), and post 1 and post 2 (25.0±27.2 mg/kg/min), but not between pretest and post 2. GIR results during the 200 mU/ m2/min insulin clamps also differed between pretest and post 1, and post 1 and post 2 but not between pretest and post 2. FDG-SUV increased between pretest (1.1±0.2) and post 1 (1.4±0.3), and remained stable between post 1 and post 2 (1.4±0.4). Conclusion: RE that increased muscle size and FDG-SUV improved IS 24 hours but not 1 week after exercise training.

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