Early postexercise muscle glycogen recovery is enhanced with a carbohydrate-protein supplement

• Published in: Journal of applied physiology (1985) 2002-10, Vol.93 (4), p.1337-1344
• Main Authors: Ivy, John L, Goforth, Harold W., Jr, Damon, Bruce M, McCauley, Thomas R, Parsons, Edward C, Price, Thomas B
• Format: Article
• Language: English
• Subjects: Adult; Biological and medical sciences; Blood Glucose - analysis; Carbohydrates; Dietary Carbohydrates - pharmacology; Dietary Proteins - pharmacology; Dietary Supplements; Epinephrine - blood; Exercise; Exercise - physiology; Fatty Acids, Nonesterified - blood; Fundamental and applied biological sciences. Psychology; Glucose; Glycogen - metabolism; Humans; Insulin; Insulin - blood; Lactic Acid - blood; Male; Muscle, Skeletal - drug effects; Muscle, Skeletal - metabolism; NMR; Norepinephrine - blood; Nuclear magnetic resonance; Proteins; Striated muscle. Tendons; Vertebrates: osteoarticular system, musculoskeletal system
• ISSN: 8750-7587; 1522-1601
• DOI: 10.1152/japplphysiol.00394.2002

1  Exercise Physiology and Metabolism Laboratory, Department of Kinesiology and Health Education, University of Texas at Austin, Austin, Texas 78712; 2  Department of Biology, Point Loma Nazarene University, San Diego, California; and 3  Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, Connecticut 06510 In the present study, we tested the hypothesis that a carbohydrate-protein (CHO-Pro) supplement would be more effective in the replenishment of muscle glycogen after exercise compared with a carbohydrate supplement of equal carbohydrate content (LCHO) or caloric equivalency (HCHO). After 2.5 ± 0.1 h of intense cycling to deplete the muscle glycogen stores, subjects ( n  = 7) received, using a rank-ordered design, a CHO-Pro (80 g CHO, 28 g Pro, 6   g fat), LCHO (80 g CHO, 6 g fat), or HCHO (108 g CHO, 6 g fat) supplement immediately after exercise (10 min) and 2 h postexercise. Before exercise and during 4 h of recovery, muscle glycogen of the vastus lateralis was determined periodically by nuclear magnetic resonance spectroscopy. Exercise significantly reduced the muscle glycogen stores (final concentrations: 40.9 ± 5.9 mmol/l CHO-Pro, 41.9 ± 5.7 mmol/l HCHO, 40.7 ± 5.0 mmol/l LCHO). After 240 min of recovery, muscle glycogen was significantly greater for the CHO-Pro treatment (88.8 ± 4.4 mmol/l) when compared with the LCHO (70.0 ± 4.0 mmol/l; P  = 0.004) and HCHO (75.5 ± 2.8 mmol/l; P   = 0.013) treatments. Glycogen storage did not differ significantly between the LCHO and HCHO treatments. There were no significant differences in the plasma insulin responses among treatments, although plasma glucose was significantly lower during the CHO-Pro treatment. These results suggest that a CHO-Pro supplement is more effective for the rapid replenishment of muscle glycogen after exercise than a CHO supplement of equal CHO or caloric content. catecholamines; glucose; lactate; insulin; nuclear magnetic resonance spectroscopy