| Inactivity, Age, and Exercise: Single Muscle Fiber Power Generation. | |
| | |
MedLine Citation:
|
PMID: 23104693 Owner: NLM Status: Publisher |
Abstract/OtherAbstract:
|
We examined the effects of mild therapeutic exercise during a period of inactivity on size and contractile functions of myosin heavy chain (MHC) type I (n=204) and type II (n=419) single fibers from the medial gastrocnemius in three age groups. Young adult (5-12mo.), middle-aged (24-31mo.) and old (32-37mo.) F344BNF1 rats were assigned to one of three groups: weight-bearing control, non-weight-bearing (NWB), and NWB plus exercise (NWBX). 14 days of hindlimb suspension was applied in NWB rats. The NWBX rats exercised on the treadmill for 15min×4X/day during the period of NWB. The NWBX did not improve peak power, but increased normalized power of MHC type I fibers in young adult rats. In MHC type II fibers, NWBX did not change peak power, Po, Vmax, and fiber size from young adult and middle-aged rats. NWBX did not improve peak power and Po, and showed a dramatic decline in Vmax and normalized power in the old rats. Collectively, mild treadmill exercise during a period of inactivity does not improve peak power of MHC type I or type II fiber from the gastrocnemius in young, middle-aged and old rats. However, NWBX is beneficial in enhancing normalized power of MHC type I fibers in young adult rats most likely due to the stimulus intensity and the ability of the individual fibers to adapt to the stimulus. In contrast, several factors such as impaired adaptation potential, inappropriate exercise intensity, or increased susceptibility to muscle damage may contribute to the lack of improvement in the older rats. |
| | |
Authors:
|
Jong-Hee Kim; Ladora V Thompson |
Related Documents
:
|
16704643 - Daily pattern of sweating and response to stress and exercise in patients with palmar h... 2762433 - Thermoregulatory response to thermal challenge in seasonal affective disorder: a prelim... 10485123 - Consistency of hand use, exercise, and sports-related injuries. |
Publication Detail:
|
Type: JOURNAL ARTICLE Date: 2012-10-25 |
Journal Detail:
|
Title: Journal of applied physiology (Bethesda, Md. : 1985) Volume: - ISSN: 1522-1601 ISO Abbreviation: J. Appl. Physiol. Publication Date: 2012 Oct |
Date Detail:
|
Created Date: 2012-10-29 Completed Date: - Revised Date: - |
Medline Journal Info:
|
Nlm Unique ID: 8502536 Medline TA: J Appl Physiol Country: - |
Other Details:
|
Languages: ENG Pagination: - Citation Subset: - |
Affiliation:
|
1University of Minnesota. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
|
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Pre-treatment with brain natriuretic peptide reduces skeletal muscle mitochondrial dysfunction and o...
Next Document: Mitochondrial morphology, topology and membrane interactions in skeletal muscle: A quantitative thre...