Multiple Axis Analysis Of Swimming Force In Relation To Swimming Speed

In the sport of swimming, champions are determined by hundredths of seconds. With a margin of victory this small, tiny adjustments to swimming stroke technique can be the deciding factor in a race. Previous research has addressed this by using sensor technology on the palms of swimmers to determine the force each hand exerts on the water. The idea behind this technology is that if a swimmer can increase the force exerted on the water, they would swim faster. However, existing research has only been able to measure resultant force, not total effective propulsive force. Recent developments in swimming sensor technology allows measurement of separate force vectors. Utilizing this technology, swimmers and coaches can better understand how to produce optimal stroke patterns to maximize effective propulsive force. PURPOSE: To determine the effects of vertical and propulsive force on swim time. METHODS: 11 middle-distance swimmers (8 female, 3 male) were equipped with an omni-directional pressure sensor on each palm. Participants were instructed to complete three 50-meter freestyle attempts at maximal effort. Participants were timed from the time their feet pushed off the starting wall to the time their hand touched the finishing wall. Swim time between trials was found to be strongly correlated using Pearson correlation tests. Therefore, only the first trial was used for multiple regression analysis to determine the effects of propulsive and vertical forces. RESULTS: Multiple regression analysis was shown to be statistically significant (R2 = 0.55, F(2, 9) = 5.54, p = 0.02). It was found that propulsive force significantly predicted swim time (β = -0.30, t(11) = -3.07, p = 0.01). However, downward force was not a significant predictor of swim time (β = -0.08, t(11) = -0.97, p = 0.37). CONCLUSIONS: Middle-distance swimmers with greater propulsive force exhibit reduced swim times in maximal 50-meter freestyle attempts.