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The Effect of Finger Positioning on the Generation of Propulsive Force



S McDonald, J E. Faller


Freestyle swimming competition is extremely fierce, as the winner of a 50- or 100- meter sprint often beats the second place swimmer by amargin of less than one hundredth of a second. So every stroke counts, especially with regard to the swimmer's technique, including the production of the largest drag force with the arms and hands and creating the least drag and resistance from the rest of the body. Most swimmers even shave their bodies, as studies show that shaved skin reduces body friction enough to create an increase in displacement of about 10% witheach stroke taken (Zumerchik, 1997). Since a human's swimming efficiency is only about 10%, primarily due to the body's lack of aerodynamicand streamlined feathers such as those on the dolphin or a fish (Zumerichik, 1997), it is all the more important for humans to analyze their style in order to optimize their performance. World records in freestyle events (in seconds) are as follows: for women, in 50 meters: 24.51, and in100 meters: 54.01; for men, in 50 meters: 21.81, and in 100 meters: 48.21 (Zumericlik, 1997). Assuming a complete stroke takes an averageof about 0.8 second, which was based on the study of several world class swimmers' performance, there are about 31 strokes taken in each 50-meter race for women and about 27 strokes of men (Ungerechts, Wilke, Reischle, 1988).
American Journal of Physics


drag force, propulsive force


McDonald, S. and Faller, J. (2021), The Effect of Finger Positioning on the Generation of Propulsive Force, American Journal of Physics (Accessed February 24, 2024)
Created October 12, 2021