Dataset Information

Exercise training-induced improvement in skeletal muscle PGC-1?-mediated fat metabolism is independent of dietary glycemic index.

ABSTRACT:

Objective

This study hypothesized that a low-glycemic diet combined with exercise would increase expression of nuclear regulators of fat transport and oxidation in insulin-resistant skeletal muscle.

Method

Nineteen subjects (64?±?1 y; 34?±?1 kg/m² ) were randomized to receive isocaloric high-glycemic-index (HiGIX; 80?±?0.6 units, n?=?10) or low-glycemic-index (LoGIX; 40?±?0.3 units, n?=?9) diets combined with supervised exercise (1 h/d, 5 d/wk at ?85% HR_max ) for 12 weeks. Insulin sensitivity was determined by hyperinsulinemic-euglycemic clamp. Skeletal muscle biopsies were obtained before and after the intervention to assess fasting gene and protein expression.

Results

Weight loss was similar for both groups (9.5?±?1.3 kg). Likewise, improvements in insulin sensitivity (P?ConclusionsAn exercise/diet program resulting in 8% to 10% weight loss improved insulin sensitivity and key molecular mechanisms in skeletal muscle that are controlled by PGC-1?. These effects were independent of the glycemic index of the diets.

SUBMITTER: Mulya A

PROVIDER: S-EPMC5373498 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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Publications

Exercise training-induced improvement in skeletal muscle PGC-1α-mediated fat metabolism is independent of dietary glycemic index.

Mulya Anny A Haus Jacob M JM Solomon Thomas P J TP Kelly Karen R KR Malin Steven K SK Rocco Michael M Barkoukis Hope H Kirwan John P JP

Obesity (Silver Spring, Md.) 20170401 4

<h4>Objective</h4>This study hypothesized that a low-glycemic diet combined with exercise would increase expression of nuclear regulators of fat transport and oxidation in insulin-resistant skeletal muscle.<h4>Method</h4>Nineteen subjects (64 ± 1 y; 34 ± 1 kg/m<sup>2</sup> ) were randomized to receive isocaloric high-glycemic-index (HiGIX; 80 ± 0.6 units, n = 10) or low-glycemic-index (LoGIX; 40 ± 0.3 units, n = 9) diets combined with supervised exercise (1 h/d, 5 d/wk at ∼85% HR<sub>max</sub> ) ...[more]

PMID: 28349667

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