Endurance exercise training decreases capillary basement membrane
width in older nondiabetic and diabetic adults.
Williamson, Joseph R., Phyllis L. Hoffmann, Wendy M. Kohrt, Robert J.
Spina, Andrew R. Coggan, John O. Holloszy.
Washington University School of Medicine, Department of Internal
Medicine, Division of Geriatrics and Gerontology, Department of
Pathology, 660 S. Euclid, Campus Box 8113, St. Louis, MO 63110
APStracts 2:0495A, 1995.
The objectives of these studies were to 1) evaluate the relationships
among age, glucose intolerance, and skeletal muscle capillary
basement membrane width (CBMW), and 2) determine the effects of
exercise training on CBMW by comparing values of young (28+/-4 yr)
and older (63+/-7 yr) athletes with those of age-matched sedentary
controls and by measuring CBMW in older men and women before and
after a 9-mo endurance exercise training program. CBMW was measured
in tissue samples obtained from the gastrocnemius muscle. CBMW in
sedentary 64+/-3 yr-olds was 25% thicker than in sedentary 24+/-3 yr
-olds. CBMW was similar in young and older athletes, and was thinner
than the CBMW of age-matched sedentary controls. There were no
differences in CBMW among older, sedentary individuals with normal or
impaired glucose tolerance or mild non-insulin-dependent diabetes
mellitus. Nine months of endurance exercise training reduced CBMW in
older men and women by 30% to 40%, to widths that were not different
from those of the young subjects; this response was independent of
glucose tolerance status. These findings suggest that habitual
exercise prevents the thickening of skeletal muscle CBM that is
characteristic of advancing age. Moreover, the thickening of CBM
appears to be readily reversed as a result of exercise training, even
in older individuals.
Received 26 May 1995; accepted in final form 27 October 1995.
APS Manuscript Number A553-5.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 30 November 95