Skip to Main content Skip to Navigation
Journal articles

Neuromechanical coupling within the human triceps surae and its consequence on individual force sharing strategies

Abstract : Little is known about the factors that influence the coordination of synergist muscles that act across the same joint, even during single-joint isometric tasks. The overall aim of this study was to determine the nature of the relationship between the distribution of activation and the distribution of force-generating capacity among the three heads of the triceps surae (soleus [SOL], gastrocnemius medialis [GM] and lateralis [GL]). Twenty volunteers performed isometric plantarflexions during which the activation of GM, GL and SOL was estimated using electromyography (EMG). Functional muscle physiological cross-sectional area (PCSA) was estimated using imaging techniques and was considered as an index of muscle-force generating capacity. The distribution of activation and PCSA among the three muscles varied greatly between participants. A significant positive correlation between the distribution of activation and the distribution of PCSA was observed when considering the two bi-articular muscles at intensities ≤50% of the maximal contraction (0.51<r<0.62). Specifically, the greater the PCSA of GM compared with GL, the stronger bias of activation to the GM. There was no significant correlation between monoarticular and biarticular muscles. A higher contribution of GM activation compared with GL activation was associated with lower triceps surae activation (−0.66 <r<−0.42) and metabolic cost (−0.74<r<−0.52) for intensities ≥30% of the maximal contraction. Considered together, an imbalance of force between the three heads was observed, the magnitude of which varied greatly between participants. The origin and consequences of these individual force-sharing strategies remain to be determined.
Document type :
Journal articles
Complete list of metadata

http://hal.univ-nantes.fr/hal-03409623
Contributor : Dépôt Nantesu St Connect in order to contact the contributor
Submitted on : Friday, October 29, 2021 - 6:56:03 PM
Last modification on : Monday, November 22, 2021 - 9:46:14 AM

Links full text

Identifiers

Collections

Citation

Marion Crouzier, Lilian Lacourpaille, Antoine Nordez, Kylie Tucker, François Hug. Neuromechanical coupling within the human triceps surae and its consequence on individual force sharing strategies. Journal of Experimental Biology, The Company of Biologists, 2018, 221 (Pt 21), ⟨10.1242/jeb.187260⟩. ⟨hal-03409623⟩

Share

Metrics

Record views

17