Journal
MUSCLE & NERVE
Volume 24, Issue 4, Pages 542-550Publisher
JOHN WILEY & SONS INC
DOI: 10.1002/mus.1038
Keywords
aging; motor unit; neural adaptation; strength
Categories
Funding
- NIA NIH HHS [NIA-AG09662] Funding Source: Medline
Ask authors/readers for more resources
Six young (mean = 23 years) and 6 older (mean = 76 years) adults participated in isometric resistance training 5 days/week for 6 weeks. The task involved isometric fifth finger abduction. Maximal motor unit discharge rates (MUDRs) were obtained from the abductor digiti minimi of each hand at 0, 2, 14, and 42 days of training using a quadrifilar needle electrode and automatic spike recognition software. In agreement with previous findings, maximal MUDR at baseline was significantly lower in older adults (P < 0.001), averaging 51.5 (+/-17.13) Hz in young and 43.3 (+/-14.88) Hz in older adults. In response to resistance training, maximal Voluntary force increased 25% in young and 33% in older subjects (P < 0.001). Maximal MUDR increased significantly (11% young, 23% older) on day 2 [F(3,36) = 2.58, P < 0.05], but in older subjects returned to baseline levels thereafter. These adaptations in abductor digiti minimi MUDR suggest a two-part response to strengthening fifth finger abduction: early disinhibition followed by altered MU activation. (C) 2001 John Wiley & Sons, Inc.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available