Racing Start Safety: Head Depth and Head Speed During Competitive Backstroke Starts

Abstract

Research on competitive swim start safety has focused on starts involving a dive from above the water surface. The purpose of this study was to determine the depths, speeds, and distances attained when executing backstroke starts, which begin in the water, and to investigate whether or not these variables are a function of age. Backstroke starts (n = 122) performed in 1.22 m of water during competition were stratified according to age group (8&U, 9-10, 11-12, 13-14, and 15&O). Dependent measures were maximum depth of the center of the head (MHD), head speed at maximum head depth (SPD), and distance from the wall at maximum head depth (DIST). Main effects were shown for age group for MHD (F = 8.86, p < 0.05), SPD (F = 4.64, p < 0.05), and DIST (F = 17.21, p < 0.05). Because they performed starts that were deeper and faster than the younger swimmers, the older swimmers seem to be at a greater risk for injury when performing backstroke starts in shallow water. The racing start may be the aspect of competitive swimming that is the most inherently risky. In support of this, a study spanning a 25-year period (1982–2007) reported 13 catastrophic injuries resulting in “permanent severe functional brain or spinal cord disability” within competitive swimming (high school and college) with all but one incident occurring during the execution of a racing start from a block (Mueller & Cantu, 2007). As a result, examination of the various parameters pertaining to the racing start, as a means of identifying the level of risk these factors represent, seems appropriate. Variables that are relevant in this regard primarily relate to the depth and speed swimmers attain during the execution of racing starts. These two variables dictate to a large extent the inertial forces generated during a start. Of the four strokes contested in competitive swimming events, three (freestyle, butterfly, and breaststroke) utilize a starting block and involve a forward dive from above the water surface and one (backstroke) is executed from within the water. To date, research on racing starts has focused exclusively on forward block starts and