|
|
||||||||
Department of Biomedical Engineering and Institute of Gerontology at the University of Michigan, Ann Arbor, Michigan
Submitted 30 March 2006 ; accepted in final form 11 May 2006
By the age of 80 yr, the skeletal muscles of men and women decrease in mass and maximum force by
30%. Severe contraction-induced injury may contribute to these age-related declines. One to two months after a 225 lengthening contraction protocol (LCP), muscles of young/adult male mice recovered completely, whereas those of old male mice sustained deficits of
15% in mass and
25% in maximum force. Although gender-related differences in the early events of contraction-induced injury have been reported, the recovery phase of muscles in old female animals has not been investigated. The hypothesis tested was that 2 mo after a severe LCP to the plantar flexor muscle group, the magnitude of recovery of mass and force for old female mice is less than that for adult female mice. The LCP was administered to muscles of adult and old, female C57BL/6 mice. At 3 days, 1 mo, and 2 mo following the LCP, maximum isometric force was measured, and muscles were removed and weighed. Two months following the LCP, the muscles of adult female mice recovered mass and force. In contrast, for old female mice, even after 2 mo, muscle masses were decreased by 11% and maximum forces by 38%. We conclude that, as reported previously for old male mice, a severe contraction-induced injury to muscles of old female mice results in prolonged deficits in mass and force.
plantar flexor muscles; lengthening contractions; sarcopenia
This article has been cited by other articles:
![]() |
G. S. Lynch, J. A. Faulkner, and S. V. Brooks Force deficits and breakage rates after single lengthening contractions of single fast fibers from unconditioned and conditioned muscles of young and old rats Am J Physiol Cell Physiol, July 1, 2008; 295(1): C249 - C256. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |