Relationship between muscle synergies and the effect of multi-joint exercise

• Project/Area Number: 17K13155
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Sports science
• Research Institution: Ritsumeikan University (2022); Kanagawa University (2017, 2019-2021); Institute of Physical and Chemical Research (2018)
• Principal Investigator: Suzuki Takahito 立命館大学, スポーツ健康科学部, 助教 (20638960)
• Project Period (FY): 2017-04-01 – 2023-03-31
• Project Status: Completed (Fiscal Year 2022)
• Budget Amount: ¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000); Fiscal Year 2020: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000); Fiscal Year 2019: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000); Fiscal Year 2018: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2017: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000)
• Keywords: 筋シナジー / 多関節運動 / 表面筋電図 / 下腿三頭筋 / 大臀筋 / 外側広筋 / 筋電図 / 大腿四頭筋

Outline of Final Research Achievements

It is important to improve coordination between muscles around various joints through training. This study aimed to reveal the muscle control for adjacent joints and non-adjacent joints and investigated the activity of the triceps surae muscles with or without activation of hip or knee extensor muscles. During isometric plantar flexor contraction, the activity of the medial gastrocnemius muscle decreased with isometric hip extensor contraction. This result suggests that the muscle activity is determined with activation of muscles at non-adjacent joints.

Academic Significance and Societal Importance of the Research Achievements

本研究では、足底屈筋群と物理的な繋がりのない股関節伸展筋群の活動によって、足底屈筋群の活動が影響を受けることを明らかにした。この結果は、足関節と股関節のように対象となる全ての関節を物理的に跨ぐ筋が存在しない場合にも、これらの関節周りの筋の活動が総合的に考慮されて、活動の量が決定されていることを示唆している。この知見は、一つの関節周りの筋を鍛えるトレーニングと、複数の関節が関わるトレーニングの効果の違いを明らかにすることに繋がる可能性がある。

Research Products

• [Journal Article] Activation of plantar flexor muscles is constrained by multiple muscle synergies rather than joint torques (2017)
  • Author(s): Takahito Suzuki, Ryuta Kinugasa, Senshi Fukashiro
  • Journal Title: PLoS ONE Volume: 12(11) Issue: 11 Pages: e0187587-e0187587
  • DOI: 10.1371/journal.pone.0187587
  • Peer Reviewed / Open Access