Clarifying the relation between force and flow during undulatory underwater swimming

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K16540
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Sports science
• Research Institution: Niigata University of Health and Welfare
• Principal Investigator: Shimojo Hirofumi 新潟医療福祉大学, 健康科学部, 講師 (50757911)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 水泳 / PIV / モーションキャプチャ / 筋電図

Outline of Final Research Achievements

We have developed a new method for three-dimensionally visualizing the flow around the swimmer's hand and foot using Particle Image Velocimetry (PIV) used in the field of fluid dynamics. Using this method, the swimmer's propulsion mechanism was investigated, and the swimmer performed complex limb-movements such as changing the stroke direction or rotation of the limb in the water, and this movement generates a vortex around the limb, It is suggested that this vortex may be the source of propulsion. Also, this vortex reflects the magnitude of the propulsive force, so if the method of this study is developed, it will be possible for the swimmer to estimate the degree of force obtained from the water.

Free Research Field

バイオメカニクス

Academic Significance and Societal Importance of the Research Achievements

これまで、水泳の腕のかきのことを「水を押す」と表現されていたが、実際には押しておらず渦を作り出して手足の周りに圧力差を生み出し、スイマーはこれを推進に利用して遊泳している。ヒトが速く泳ぐためには、作用反作用のように力任せに水を押せば進めるのではなく、渦をどうやって作るかがカギとなり、水泳指導法のパラダイムシフトにつながる。