Effect of short-term exercise training on intramyocellular lipid content.
The purpose of this study was to investigate the influence of exercise training on intramyocellular lipid (IMCL) content and test the hypothesis that the effect of endurance-oriented exercise training on IMCL is dependent on characteristics of the population studied. Lean (N = 11, body mass index (BMI) = 22.2 ± 0.7 kg·m⁻²), obese (N = 14, BMI = 38.8 ± 1.7 kg·m⁻²), and type 2 diabetic (N = 9, BMI = 35.5 ± 2.5 kg·m⁻²) participants were examined before and after 10 consecutive days of endurance-oriented (60 min·day⁻¹ at ~70% [Formula: see text]O(2peak)) exercise training. IMCL and muscle glycogen were measured by Oil-Red-O and periodic acid - Schiff staining, respectively. The results indicated that IMCL was elevated (p < 0.05) in the obese and diabetic groups compared with the lean subjects prior to training. After training, IMCL content decreased (-35%) in the participants with type 2 diabetes; there were no changes in IMCL in the lean or obese groups. Muscle glycogen content was lower in the diabetic subjects than in the lean subjects both before and after training. These data indicate that changes in IMCL with exercise training do not exhibit a universal response but rather depend on the metabolic status of the population studied.
Department of Exercise and Sports Science, East Carolina University, Greenville, NC 27858, USA. sudip.bajpeyi@pbrc.edu
Sudip
S
Bajpeyi
Melissa A
MA
Reed
Sara
S
Molskness
Christopher
C
Newton
Charles J
CJ
Tanner
Jennifer S
JS
McCartney
Joseph A
JA
Houmard
D000328:Adult; D001707:Biopsy, Needle; D015992:Body Mass Index; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism* / Q000473:pathology; D015444:Exercise; D005260:Female; D006003:Glycogen / Q000378:metabolism; D006801:Humans; D050356:Lipid Metabolism; D008297:Male; D008875:Middle Aged; D018656:Muscle Fibers, Fast-Twitch / Q000378:metabolism / Q000473:pathology; D018657:Muscle Fibers, Slow-Twitch / Q000378:metabolism / Q000473:pathology; D009765:Obesity / Q000378:metabolism* / Q000473:pathology; D010101:Oxygen Consumption; D005082:Physical Exertion; D052097:Quadriceps Muscle / Q000378:metabolism* / Q000473:pathology; D057185:Sedentary Behavior
D006003:Glycogen