Load distribution within the contracting hamstring muscles: relevance to strain injuries in sport

2018 Fiscal Year Annual Research Report

• Project/Area Number: 17F17412
• Research Institution: Waseda University
• Principal Investigator: 川上 泰雄 早稲田大学, スポーツ科学学術院, 教授 (60234027)
• Co-Investigator(Kenkyū-buntansha): EVANGELIDIS PAVLOS 早稲田大学, スポーツ科学学術院, 外国人特別研究員
• Project Period (FY): 2017-11-10 – 2020-03-31
• Keywords: muscle strain injury / hamstrings / ultrasonography

Outline of Annual Research Achievements

The proposed research is to better understand the mechanisms of hamstring strain injuries. The specific aims are: 1) to examine the load distribution between the individual hamstring muscles at different levels of muscle activation and contraction modes (concentric, isometric, and eccentric), 2) To examine the effect of neuromuscular fatigue on load distribution between hamstring muscles at different contraction modes. The third and final aim has been slightly amended based on the findings of the previous studies and now focuses on the examination of the site-specific (proximal-middle-distal) differences in localised strains between hamstrings during isometric and eccentric contractions. In FY2017 and 2018, the first two aims were addressed while the final aim will be investigated in FY2019.

Current Status of Research Progress

2: Research has progressed on the whole more than it was originally planned.

Reason

The data collection and analysis of the previous two studies has been completed. For the first study, an abstract has already been submitted (review pending) to the XXVII Congress of the International Society of Biomechanics/ 43th Annual Meeting of the American Society of Biomechanics, while an abstract of the second study is currently being prepared for submission to the Rocky Mountain Muscle Symposium 2019. In addition, manuscripts for both studies are in preparation.

Strategy for Future Research Activity

In FY2019, the pilot testing and main data collection for the final study will be completed (May-mid August) followed by data analysis which is expected to be completed by late September. In the remaining months, a manuscript of the final study will be prepared.