How do swimmers control their front crawl swimming velocity? Current knowledge and gaps from hydrodynamic perspectives

Abstract

The aim of this study was to review the literature on front crawl swimming biomechanics, focusing on propulsive and resistive forces at different swimming velocities. Recent studies show that the resistive force increases in proportion to the cube of the velocity, which implies that a proficient technique to miminise the resistive (and maximise the propulsive) force is particularly important in sprinters. To increase the velocity in races, swimmers increase their stroke frequency. However, experimental and simulation studies have revealed that there is a maximum frequency beyond which swimmers cannot further increase swimming velocity due to a change in the angle of attack of the hand that reduces its propulsive force. While the results of experimental and simulation studies are consistent regarding the effect of the arm actions on propulsion, the findings of investigations into the effect of the kicking motion are conflicting. Some studies have indicated a positive effect of kicking on propulsion at high swimming velocities while the others have yielded the opposite result. Therefore, this review contributes to knowledge of how the upper-limb propulsion can be optimised and indicates a need for further investigation to understand how the kicking action can be optimised in front crawl swimming.

Relationship Between Hand Kinematics, Hand Hydrodynamic Pressure Distribution and Hand Propulsive Force in Sprint Front Crawl Swimming

“…In front crawl swimming, the arms exert greater propulsive force than the legs (Cohen et al, 2017 ), and of the upper arms, forearms and hands, it has been suggested that the hands exert the largest propulsive force (Toussaint et al, 2002 ; Samson et al, 2017 ; Takagi et al, 2021 ). Therefore, the present experiment was conducted based on the assumption that the force exerted by the segments other than the hand would be negligible.…”

“…It has been suggested that the arms exert more propulsion than the legs in front crawl swimming (Cohen et al, 2017 ) and that the hands contribute the most propulsion among the upper arm, forearm and hand (Toussaint et al, 2002 ; Samson et al, 2017 ; Takagi et al, 2021 ). Hence, the magnitude of propulsion in hand is related to swimming velocity (Tsunokawa et al, 2019b ).…”

Differences in Race Characteristics between World-Class Individual-Medley and Stroke-Specialist Swimmers

“…Both male and female breaststroke-specialists showed a 3.0–4.5% faster clean-swimming speed during the third lap of their 200 m race compared to IM swimmers’ breaststroke lap. Swimming speed is the product of distance per stroke and stroke rate [ 14 , 15 ], and swimmers generally control their speed by increasing stroke rate rather than distance per stroke [ 16 , 17 ]. In other words, higher stroke rate increases exercise intensity, thus energy cost, which is the energy expenditure required to swim a given distance [ 16 ].…”

Vision-Based System for Automated Estimation of the Frontal Area of Swimmers: Towards the Determination of the Instant Active Drag: A Pilot Study

“…The most recent work of Takagi et al [16] reviewed the literature on front crawl, focusing on propulsive and resistive forces at different swimming velocities. The relationships between energetic, biomechanical, and fluid dynamics indices in competitive swimming were established factors that determine the mean of the instantaneous magnitudes of hand velocity over some time.…”