Muscle glycogen supercompensation: absence of a gender-related difference.
Recently it has been reported that women do not have the capacity to accumulate supranormal levels of muscle glycogen when subjected to a carbohydrate (CHO) loading regimen [Tarnopolsky et al. (1995) J Appl Physiol 78:1360-1368]. Since, in this study, CHO intake relative to body mass in the female subjects was much lower than that in males, our primary aim was to re-examine this issue using subjects fed comparable amounts of CHO. Endurance-trained female and male subjects ingested 12 g CHO x kg(-1) lean body mass day(-1) in conjunction with the cessation of their daily physical training. A 3-day exposure to this diet resulted in a marked rise in muscle glycogen levels from [mean (SD)] 108 (15) mmol x kg(-1) wet weight to 193 (14) mmol x kg(-1) wet weight and 111 (16) m mol x kg(-1) wet weight to 202 (20) mmol x kg(-1) wet weight in the female participants during the post-menstrual and pre-menstrual phases of their menstrual cycle, respectively, and from 109 (27) mmol x kg(-1) wet weight to 183 (25) mmol x kg(-1) wet weight in males. We conclude that (1) female athletes have the capacity to accumulate supranormal levels of muscle glycogen, and (2) when exercise-trained males and females are fed comparable amounts of CHO relative to lean body mass, there is no gender-related difference in their ability to accumulate supranormal levels of muscle glycogen.
James
A P
AP
Department of Biochemistry, University of Western Australia, Nedlands, Australia.
Lorraine
M
M
Cullen
D
D
Goodman
C
C
Dawson
B
B
Palmer
T N
TN
Fournier
P A
PA
D000328:Adult; D004040:Dietary Carbohydrates / Q000493:pharmacokinetics; D005260:Female; D006003:Glycogen / Q000378:metabolism*; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000378:metabolism*; D010807:Physical Endurance / Q000502:physiology; D012727:Sex Characteristics
D004040:Dietary Carbohydrates; D006003:Glycogen