The optimal downhill slope for acute overspeed running.

PURPOSE This study evaluated a variety of downhill slopes in an effort to determine the optimal slope for overspeed running. METHODS Thirteen NCAA Division III college athletes who participated in soccer, track, and football ran 40-yd (36.6-m) sprints, on downhill slopes of 2.1 degrees , 3.3 degrees , 4.7 degrees , 5.8 degrees , and 6.9 degrees in random order. All sprints were timed using the Brower Timing System Speedtrap II. Data were analyzed with SSPS 15.0. A 1-way repeated-measures analysis of variance revealed significant main effects for the test slopes (P = .000). Bonferroni-adjusted pairwise comparisons determined that there were a number of differences between the hill slopes. RESULTS Analysis reveals that 40-yd sprints performed on hill slopes of approximately 5.8 degrees were optimal compared with flatland running and the other slopes assessed (P < .05). Sprinting on a 5.8 degrees slope increased the subjects' maximal speed by an average of 0.35 s, resulting in a 6.5% +/- 4.0% decrease in 40-yd sprint time compared with flatland running. Compared with the 4.7 degrees slope, the 5.8 degrees slope yielded a 0.10-s faster 40-yd sprint time, resulting in a 1.9% increase in speed. CONCLUSIONS Those who train athletes for speed should use or develop overspeed hills with slopes of approximately 5.8 degrees to maximize acute sprinting speed. The results of this study bring into question previous recommendations to use hills of 3 degrees downhill slope for this form of overspeed training.