Single skeletal muscle fiber elastic and contractile characteristics in young and older men
Research output: Contribution to journal › Journal article › Research › peer-review
The current investigation was designed to: (a) assess the impact of aging on elastic characteristics of single skeletal muscle fibers from young (N = 6) and older men (N = 6); and (b) correlate the potential changes, with the fiber contractile properties. Chemically skinned single muscle fibers (n = 235) from vastus lateralis muscle were maximally activated. Maximal force and cross-sectional area were measured, and specific force calculated. The slack test was used to measure maximal unloaded shortening velocity. A quick release of 0.15% of fiber length was applied to determine instantaneous stiffness. The myosin heavy chain isoform composition of each single fiber was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Aging induces changes in both fiber elasticity (i.e., increased instantaneous stiffness) and contractility (i.e., reduced specific force and unloaded shortening velocity) in type I and IIa fibers. However, the changes in fiber stiffness may not directly influence contractile characteristics alterations.
Original language | English |
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Journal | Journals of Gerontology - Series A Biological Sciences and Medical Sciences |
Volume | 62 |
Issue number | 4 |
Pages (from-to) | 375-381 |
Number of pages | 7 |
ISSN | 1079-5006 |
DOIs | |
Publication status | Published - Apr 2007 |
ID: 245665646