Effect of mild exercise training on glucose effectiveness in healthy men.
OBJECTIVE
To detect whether mild exercise training improves glucose effectiveness (S(G)), which is the ability of hyperglycemia to promote glucose disposal at basal insulin, in healthy men.


METHODS
Eight healthy men (18-25 years of age) underwent ergometer training at lactate threshold (LT) intensity for 60 min/day for 5 days/week for 6 weeks. An insulin-modified intravenous glucose tolerance test was performed before as well as at 16 h and 1 week after the last training session. S(G) and insulin sensitivity (S(I)) were estimated using a minimal-model approach.


RESULTS
After the exercise training, VO(2max) and VO(2) at LT increased by 5 and 34%, respectively (P < 0.05). The mild exercise training improves S(G) measured 16 h after the last training session, from 0.018 +/- 0.002 to 0.024 +/- 0.001 min(-1) (P < 0.05). The elevated S(G) after exercise training tends to be maintained regardless of detraining for 1 week (0.023 +/- 0.002 min(-1), P = 0.09). S(I) measured at 16 h after the last training session significantly increased (pre-exercise training, 13.9 +/- 2.2; 16 h, 18.3 +/- 2.4, x10(-5). min(-1). pmol/l(-1), P < 0.05) and still remained elevated 1 week after stopping the training regimen (18.6 +/- 2.2, x10(-5). min(-1). pmol/l(-1), P < 0.05).


CONCLUSIONS
Mild exercise training at LT improves S(G) in healthy men with no change in the body composition. Improving not only S(I) but also S(G) through mild exercise training is thus considered to be an effective method for preventing glucose intolerance.
Nishida
Y
Y
Research Center of Health, Physical Fitness, and Sports, Nagoya University, Nagoya, Japan.
Higaki
Y
Y
Tokuyama
K
K
Fujimi
K
K
Kiyonaga
A
A
Shindo
M
M
Sato
Y
Y
Tanaka
H
H
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism*; D015444:Exercise / Q000502:physiology*; D005215:Fasting; D005947:Glucose / Q000378:metabolism*; D005951:Glucose Tolerance Test; D006801:Humans; D007328:Insulin / Q000097:blood; D008297:Male; D010101:Oxygen Consumption; D010806:Physical Education and Training; D010809:Physical Fitness / Q000502:physiology*; D012016:Reference Values
D001786:Blood Glucose; D007328:Insulin; D005947:Glucose