Int J Sports Med 1989; 10: S63-S67
DOI: 10.1055/s-2007-1024955
© Georg Thieme Verlag Stuttgart · New York

Glycogen Synthesis During Exercise and Rest with Carbohydrate Feeding in Males and Females*

H. Kuipers, W. H. M. Saris, F. Brouns, H. A. Keizer, C. ten Bosch
  • Dept. Physiology, University of Limburg, Maastricht, The Netherlands
* This study was supported by research grants of Wander Ltd., Bern, Switzerland.
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Publication History

Publication Date:
14 March 2008 (online)


Since it has been demonstrated that endurance-trained cyclists are able to synthesize glycogen during mild exercise, glycogen synthesis was investigated in non-endurance-trained males and females as well. Seven males and nine females exercised on a cycle ergometer to deplete muscle glycogen. After the exhaustive exercise and taking a muscle biopsy, the males either exercised 2.5 h at 40% of maximal work load (trial A) or rested for 2.5 h (trial B). In both trials the subjects drank a 25% maltodextrinfructose solution. After 2.5 h of exercise or rest, a second muscle biopsy was taken for determination of glycogen and for histochemistry (ATPase and PAS). In the females glycogen synthesis was only studied during 2.5 h rest, after prior glycogen depletion. In the male subjects, during mild exercise with carbohydrate feeding muscle glycogen did not increase. During rest muscle glycogen increased in the males from 123 ± 49 mmol/kg DW at exhaustion to 229 ± 70 mmol/kg DW (P < 0.001), resulting in a net increase of 42 mmol/kg DW/h. Glycogen synthesis during rest occurred both in type I and type II fibers. In the females, during 2.5 h of rest, muscle glycogen increased from 130 ± 56 mmol/kg DW at exhaustion to 224 ± 51 mmol/kg DW, resulting in a net increase of 37 mmol/kg DW/h. The results demonstrate that glycogen synthesis during mild exercise does not occur in non-endurance-trained athletes, whereas in the resting state glycogen synthesis in non-endurance-trained males is not different from endurance-trained cyclists. In addition, glycogen synthesis during rest is similar in males and females.