PMID- 33763775
OWN - NLM
STAT- MEDLINE
DCOM- 20211028
LR  - 20231107
IS  - 2509-2723 (Electronic)
IS  - 2509-2715 (Print)
IS  - 2509-2723 (Linking)
VI  - 43
IP  - 4
DP  - 2021 Aug
TI  - Lifelong exercise is associated with more homogeneous motor unit potential 
      features across deep and superficial areas of vastus lateralis.
PG  - 1555-1565
LID - 10.1007/s11357-021-00356-8 [doi]
AB  - Motor unit (MU) expansion enables rescue of denervated muscle fibres helping to 
      ameliorate age-related muscle atrophy, with evidence to suggest master athletes 
      are more successful at this remodelling. Electrophysiological data has suggested 
      MUs located superficially are larger than those located deeper within young 
      muscle. However, the effects of ageing and exercise on MU heterogeneity across 
      deep and superficial aspects of vastus lateralis (VL) remain unclear. 
      Intramuscular electromyography was used to record individual MU potentials (MUPs) 
      and near fibre MUPs (NFMs) from deep and superficial regions of the VL during 25% 
      maximum voluntary contractions, in 83 males (15 young (Y), 17 young athletes 
      (YA), 22 old (O) and 29 master athletes (MA)). MUP size and complexity were 
      assessed using area and number of turns, respectively. Multilevel mixed effects 
      linear regression models were performed to investigate the effects of depth in 
      each group. MUP area was greater in deep compared with superficial MUs in Y 
      (p<0.001) and O (p=0.012) but not in YA (p=0.071) or MA (p=0.653). MUP amplitude 
      and NF MUP area were greater, and MUPs were more complex in deep MUPs from Y, YA 
      and O (all p<0.05) but did not differ across depth in MA (all p>0.07). These data 
      suggest MU characteristics differ according to depth within the VL which may be 
      influenced by both ageing and exercise. A more homogenous distribution of MUP 
      size and complexity across muscle depths in older athletes may be a result of a 
      greater degree of age-related MU adaptations.
CI  - (c) 2021. The Author(s).
FAU - Jones, Eleanor J
AU  - Jones EJ
AD  - Clinical, Metabolic and Molecular Physiology, MRC-Versus Arthritis Centre for 
      Musculoskeletal Ageing Research, National Institute for Health Research (NIHR) 
      Nottingham Biomedical Research Centre, University of Nottingham, Nottingham, UK.
FAU - Piasecki, Jessica
AU  - Piasecki J
AD  - Musculoskeletal Physiology Research Group, Sport, Health and Performance 
      Enhancement Research Centre, School of Science and Technology, Nottingham Trent 
      University, Nottingham, UK.
FAU - Ireland, Alex
AU  - Ireland A
AD  - Department of Life Sciences, Musculoskeletal Science and Sports Medicine Research 
      Centre, Manchester Metropolitan University, Manchester, UK.
FAU - Stashuk, Daniel W
AU  - Stashuk DW
AD  - Department of Systems Design Engineering, University of Waterloo, Waterloo, 
      Ontario, Canada.
FAU - Atherton, Philip J
AU  - Atherton PJ
AD  - Clinical, Metabolic and Molecular Physiology, MRC-Versus Arthritis Centre for 
      Musculoskeletal Ageing Research, National Institute for Health Research (NIHR) 
      Nottingham Biomedical Research Centre, University of Nottingham, Nottingham, UK.
FAU - Phillips, Bethan E
AU  - Phillips BE
AD  - Clinical, Metabolic and Molecular Physiology, MRC-Versus Arthritis Centre for 
      Musculoskeletal Ageing Research, National Institute for Health Research (NIHR) 
      Nottingham Biomedical Research Centre, University of Nottingham, Nottingham, UK.
FAU - McPhee, Jamie S
AU  - McPhee JS
AD  - Department of Sport and Exercise Sciences, Musculoskeletal Science and Sports 
      Medicine Research Centre, Manchester Metropolitan University, Manchester, UK.
FAU - Piasecki, Mathew
AU  - Piasecki M
AUID- ORCID: 0000-0002-7804-4631
AD  - Clinical, Metabolic and Molecular Physiology, MRC-Versus Arthritis Centre for 
      Musculoskeletal Ageing Research, National Institute for Health Research (NIHR) 
      Nottingham Biomedical Research Centre, University of Nottingham, Nottingham, UK. 
      Mathew.piasecki@nottingham.ac.uk.
LA  - eng
GR  - MR/K025252/1/MRC_/Medical Research Council/United Kingdom
GR  - MR/P021220/1/MRC_/Medical Research Council/United Kingdom
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20210324
PL  - Switzerland
TA  - Geroscience
JT  - GeroScience
JID - 101686284
SB  - IM
MH  - Aged
MH  - Aging
MH  - Electromyography
MH  - Humans
MH  - Male
MH  - *Motor Neurons
MH  - Muscle Fibers, Skeletal
MH  - *Quadriceps Muscle
PMC - PMC8492837
OTO - NOTNLM
OT  - Electromyography
OT  - Master athlete
OT  - Motor unit
OT  - Sarcopenia
COIS- The authors declare no competing interests.
EDAT- 2021/03/26 06:00
MHDA- 2021/10/29 06:00
PMCR- 2021/03/24
CRDT- 2021/03/25 06:41
PHST- 2020/12/29 00:00 [received]
PHST- 2021/03/10 00:00 [accepted]
PHST- 2021/03/26 06:00 [pubmed]
PHST- 2021/10/29 06:00 [medline]
PHST- 2021/03/25 06:41 [entrez]
PHST- 2021/03/24 00:00 [pmc-release]
AID - 10.1007/s11357-021-00356-8 [pii]
AID - 356 [pii]
AID - 10.1007/s11357-021-00356-8 [doi]
PST - ppublish
SO  - Geroscience. 2021 Aug;43(4):1555-1565. doi: 10.1007/s11357-021-00356-8. Epub 2021 
      Mar 24.