Failure to expand the motor unit size to compensate for declining motor unit numbers distinguishes sarcopenic from non-sarcopenic older men
Sarcopenia results from the progressive loss of skeletal muscle mass and reduced function in older age. It is likely to be associated with the well‐documented reduction of motor unit numbers innervating limb muscles and the increase in size of surviving motor units via reinnervation of denervated fi...
| Main Authors: | , , , , , , , |
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| Format: | Article |
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Wiley
2018
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| Online Access: | https://eprints.nottingham.ac.uk/51831/ |
| _version_ | 1848798584490688512 |
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| author | Piasecki, M. Ireland, A. Piasecki, J. Stashuk, D.W. Swiecicka, A. Rutter, M.K. Jones, D.A. McPhee, J.S. |
| author_facet | Piasecki, M. Ireland, A. Piasecki, J. Stashuk, D.W. Swiecicka, A. Rutter, M.K. Jones, D.A. McPhee, J.S. |
| author_sort | Piasecki, M. |
| building | Nottingham Research Data Repository |
| collection | Online Access |
| description | Sarcopenia results from the progressive loss of skeletal muscle mass and reduced function in older age. It is likely to be associated with the well‐documented reduction of motor unit numbers innervating limb muscles and the increase in size of surviving motor units via reinnervation of denervated fibres. However, no evidence exists to confirm the extent of motor unit remodelling in sarcopenic individuals. The aim of the present study was to compare motor unit size and number between young (n = 48), non‐sarcopenic old (n = 13), pre‐sarcopenic (n = 53) and sarcopenic (n = 29) men. Motor unit potentials (MUPs) were isolated from intramuscular and surface EMG recordings. The motor unit numbers were reduced in all groups of old compared with young men (all P < 0.001). MUPs were higher in non‐sarcopenic and pre‐sarcopenic men compared with young men (P = 0.039 and 0.001 respectively), but not in the vastus lateralis of sarcopenic old (P = 0.485). The results suggest that extensive motor unit remodelling occurs relatively early during ageing, exceeds the loss of muscle mass and precedes sarcopenia. Reinnervation of denervated muscle fibres probably expands the motor unit size in the non‐sarcopenic and pre‐sarcopenic old, but not in the sarcopenic old. These findings suggest that a failure to expand the motor unit size distinguishes sarcopenic from pre‐sarcopenic muscles. |
| first_indexed | 2025-11-14T20:22:06Z |
| format | Article |
| id | nottingham-51831 |
| institution | University of Nottingham Malaysia Campus |
| institution_category | Local University |
| last_indexed | 2025-11-14T20:22:06Z |
| publishDate | 2018 |
| publisher | Wiley |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | nottingham-518312020-05-04T19:35:23Z https://eprints.nottingham.ac.uk/51831/ Failure to expand the motor unit size to compensate for declining motor unit numbers distinguishes sarcopenic from non-sarcopenic older men Piasecki, M. Ireland, A. Piasecki, J. Stashuk, D.W. Swiecicka, A. Rutter, M.K. Jones, D.A. McPhee, J.S. Sarcopenia results from the progressive loss of skeletal muscle mass and reduced function in older age. It is likely to be associated with the well‐documented reduction of motor unit numbers innervating limb muscles and the increase in size of surviving motor units via reinnervation of denervated fibres. However, no evidence exists to confirm the extent of motor unit remodelling in sarcopenic individuals. The aim of the present study was to compare motor unit size and number between young (n = 48), non‐sarcopenic old (n = 13), pre‐sarcopenic (n = 53) and sarcopenic (n = 29) men. Motor unit potentials (MUPs) were isolated from intramuscular and surface EMG recordings. The motor unit numbers were reduced in all groups of old compared with young men (all P < 0.001). MUPs were higher in non‐sarcopenic and pre‐sarcopenic men compared with young men (P = 0.039 and 0.001 respectively), but not in the vastus lateralis of sarcopenic old (P = 0.485). The results suggest that extensive motor unit remodelling occurs relatively early during ageing, exceeds the loss of muscle mass and precedes sarcopenia. Reinnervation of denervated muscle fibres probably expands the motor unit size in the non‐sarcopenic and pre‐sarcopenic old, but not in the sarcopenic old. These findings suggest that a failure to expand the motor unit size distinguishes sarcopenic from pre‐sarcopenic muscles. Wiley 2018-05-01 Article PeerReviewed Piasecki, M., Ireland, A., Piasecki, J., Stashuk, D.W., Swiecicka, A., Rutter, M.K., Jones, D.A. and McPhee, J.S. (2018) Failure to expand the motor unit size to compensate for declining motor unit numbers distinguishes sarcopenic from non-sarcopenic older men. Journal of Physiology, 596 (9). pp. 1627-1637. ISSN 1469-7793 https://doi.org/10.1113/JP275520 doi:10.1113/JP275520 doi:10.1113/JP275520 |
| spellingShingle | Piasecki, M. Ireland, A. Piasecki, J. Stashuk, D.W. Swiecicka, A. Rutter, M.K. Jones, D.A. McPhee, J.S. Failure to expand the motor unit size to compensate for declining motor unit numbers distinguishes sarcopenic from non-sarcopenic older men |
| title | Failure to expand the motor unit size to compensate for declining motor unit numbers distinguishes sarcopenic from non-sarcopenic older men |
| title_full | Failure to expand the motor unit size to compensate for declining motor unit numbers distinguishes sarcopenic from non-sarcopenic older men |
| title_fullStr | Failure to expand the motor unit size to compensate for declining motor unit numbers distinguishes sarcopenic from non-sarcopenic older men |
| title_full_unstemmed | Failure to expand the motor unit size to compensate for declining motor unit numbers distinguishes sarcopenic from non-sarcopenic older men |
| title_short | Failure to expand the motor unit size to compensate for declining motor unit numbers distinguishes sarcopenic from non-sarcopenic older men |
| title_sort | failure to expand the motor unit size to compensate for declining motor unit numbers distinguishes sarcopenic from non-sarcopenic older men |
| url | https://eprints.nottingham.ac.uk/51831/ https://eprints.nottingham.ac.uk/51831/ https://eprints.nottingham.ac.uk/51831/ |