Effect of weight reduction, obesity predisposition, and aerobic fitness on skeletal muscle mitochondrial function.

Academic Article

Abstract

  • We used (31)P magnetic resonance spectroscopy to measure maximal mitochondrial function in 12 obesity-prone women before and after diet-induced weight reduction and in 12 matched, never-obese, and 7 endurance-trained controls. Mitochondrial function was modeled after maximum-effort plantar flexion from the phosphocreatine recovery time constant (TC(PCr)), the ADP recovery time constant (TC(ADP)), and the rate of change in PCr during the first 14 s of recovery (OxPhos). Weight reduction was not associated with a significant change in mitochondrial function by TC(PCr), TC(ADP), or OxPhos. Mitochondrial function was not different between postobese and never-obese controls by TC(PCr) [35.1 +/- 2.5 (SE) vs. 34.6 +/- 2.5 s], TC(ADP) (22.9 +/- 1.8 vs. 21.2 +/- 1.8 s), or OxPhos (0.26 +/- 0. 03 vs. 0.25 +/- 0.03 mM ATP/s), postobese vs. never-obese, respectively. However, TC(ADP) was significantly faster (14.5 +/- 2. 3 s), and OxPhos was significantly higher (0.38 +/- 0.04 mM ATP/s) in the endurance-trained group. These results suggest that maximal mitochondrial function is not impaired in normal-weight obesity-prone women relative to their never-obese counterparts but is increased in endurance-trained women.
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    Published In

    Keywords

  • Adult, Disease Susceptibility, Exercise, Female, Humans, Isometric Contraction, Magnetic Resonance Spectroscopy, Mitochondria, Muscle, Muscle, Skeletal, Obesity, Oxygen Consumption, Physical Endurance, Physical Fitness, Weight Loss
  • Digital Object Identifier (doi)

    Author List

  • Larson-Meyer DE; Newcomer BR; Hunter GR; McLean JE; Hetherington HP; Weinsier RL
  • Start Page

  • E153
  • End Page

  • E161
  • Volume

  • 278
  • Issue

  • 1