Abstract | BACKGROUND: METHODS: We evaluated the effect of 9 mo of vigorous endurance exercise training (approximately 80% of maximal heart rate) on the glucose-stimulated insulin response and glucose disposal rate, using the hyperglycemic clamp procedure, in 12 people aged 65 +/- 1 yr (mean +/- SE) with normal glucose tolerance. The post-training hyperglycemic clamps were performed approximately 16 h after a usual exercise session. RESULTS: VO2max increased approximately 23% in response to the exercise program. The plasma insulin concentration (I) during hyperglycemia (180 mg.dL-1) was significantly lower (mean 36 +/- 6 microU.mL-1 before vs 26 +/- 5 microU.mL-1 after; p < .05) after the exercise program. Insulin action was improved by the exercise, as the glucose disposal rate (M) during hyperglycemia was unchanged despite the blunted insulin response, resulting in an increase in the M/I ratio from 24 +/- 5 to 30 +/- 5 (p < .05), a value similar to the M/I ratio of 33 +/- 4 found in normally active young subjects. CONCLUSION: These results provide evidence that regular exercise is effective in reducing hyperinsulinemia and improving insulin action in 65-yr-olds to levels typical of young people.
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Authors | J P Kirwan, W M Kohrt, D M Wojta, R E Bourey, J O Holloszy |
Journal | Journal of gerontology
(J Gerontol)
Vol. 48
Issue 3
Pg. M84-90
(May 1993)
ISSN: 0022-1422 [Print] United States |
PMID | 8482816
(Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S.)
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Chemical References |
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Topics |
- Age Factors
- Aged
- Blood Glucose
(analysis)
- Body Composition
- Exercise
- Female
- Glucose Clamp Technique
- Humans
- Insulin
(blood)
- Male
- Middle Aged
- Physical Fitness
- Weight Loss
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