Abstract
Purpose: Aging is associated with a decline in muscle volume, power output, and the velocity at which peak power (V-opt) occurs. The current study aimed to examine the relationship between lower-limb power output characteristics, muscle myosin heavy chain (MHC) composition, and lean limb volume. Methods: Lower-limb power output during repeated efforts on an inertial sprint cycle and single-leg thrusts on the modified Nottingham power rig was studied in seven young and seven old males in relation to muscle MHC isoform composition of the vastus lateralis. Results: Older subjects produced significantly lower power outputs and V-opt under all conditions (P <0.01) and had lower proportions of fast MHC isoforms (P <0.05). Peak power output during cycling was significantly related to lower-limb lean volume (r = 0.92, P <0.05), whereas V-opt during sprint cycling was closely related to vastus lateralis MHC-II composition (r = 0.80, P <0.05). Conclusions: These results provide further evidence of the importance of fast myosin isoform composition in the maintenance of dynamic muscle function in later life and particularly for maximal cycling performance
| Original language | English |
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| Pages (from-to) | 1601 - 1607 |
| Number of pages | 7 |
| Journal | Medicine and Science in Sports and Exercise |
| Volume | 38 |
| Issue number | 9 |
| DOIs | |
| Publication status | Published - Sept 2006 |