Effect of a two-month detraining on glucose tolerance and insulin sensitivity in athletes--link to adrenal steroid hormones.
Reduction in physical activity has been demonstrated to associate with the increased risk in insulin resistance and type 2 diabetes. To determine whether alteration in insulinemia, due to abstention from regular exercise training, is associated with changes in serum dehydroepiandrosterone sulfate (DHEA-S) and cortisol, 18 highly trained badminton players (21.2 +/- 0.3 years) were enrolled into a 2-month detraining study. Fasting serum insulin, glucose, DHEA-S, and cortisol were determined at trained state and at day 60 of detraining. Glucose tolerance and insulin sensitivity were assessed by an oral glucose tolerance test (OGTT). The 2-month detraining increased fasting glucose and insulin concentrations and body weight slightly, but did not significantly affect glucose tolerance and insulin response curve, in which 10 subjects had increased and 8 subjects had slightly decreased in the area under curve for insulin (IAUC). In the subjects with increased IAUC, serum cortisol was also elevated (from 0.44 +/- 0.07 to 0.83 +/- 0.26 U/l, P < 0.05) in parallel, and serum creatine kinase (CK) was unaltered during detraining. Whereas in the subjects with decreased IAUC, serum cortisol (from 0.51 +/- 0.19 to 0.54 +/- 0.14 U/l, no significance) was not changed and serum creatine kinase (from 461 +/- 179 to 151 +/- 21 U/l) was decreased during detraining. Two groups of detrained subjects exhibited a similar reduction in serum DHEA-S levels and slight elevation in body weight. The novel finding of the study is that the changes in serum cortisol, but not DHEA-S, were associated with the change in insulin sensitivity during early phase of lifestyle change from physically active to sedentary, and this response appears to be varied individually among athletes.
Wang
Pin-Tai
PT
Laboratory of Exercise Biochemistry, Taipei Physical Education College, Taipei 105, Taiwan, R.O.C.
Chiang
I-Tsun
IT
Lin
Chih-Yuan
CY
Hou
Chien-Wen
CW
Chen
Chung-Yu
CY
Lee
Hsing-Hao
HH
Chang
Wei-Hsiang
WH
Kuo
Chia-Hua
CH
D000302:Adrenal Cortex / Q000378:metabolism; D000328:Adult; D019540:Area Under Curve; D001786:Blood Glucose / Q000378:metabolism; D015992:Body Mass Index; D050260:Carbohydrate Metabolism / Q000502:physiology; D003402:Creatine Kinase / Q000097:blood; D019314:Dehydroepiandrosterone Sulfate / Q000097:blood*; D015444:Exercise / Q000502:physiology*; D005951:Glucose Tolerance Test; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance / Q000502:physiology*; D008019:Life Style
D001786:Blood Glucose; D007328:Insulin; D019314:Dehydroepiandrosterone Sulfate; D003402:Creatine Kinase; D006854:Hydrocortisone