Document Type



PURPOSE: The aim of this study was to examine the speed (yard/sec) and power (Inertial Power Units) of an athlete via the modalities of a 20-yard dash (yards/sec), a broad jump (m), and a portable conical pulley (CP) (VersaPulley, Santa Ana, CA; Inertia 0.27 kg· m2) device. Subjects were tested after completing resistance versus non- resistance based warm-ups. Research of overall effectiveness of warm-ups in direct correlation to athletic performance has been field-tested in a variety of different forms. This study was designed to create a baseline for each athlete and then take the same warm -up and by applying resistance, determine the improvement on straight line speed and power output via a broad jump and the Versa Pulley machine. METHODS: Fourteen subjects performed two assessments separated by 1 week. The experiment consisted of a two-week testing period. Upon arrival, anthropometric measurements of the subjects were taken. During the first week, both groups went through the same warm-up with no resistance. Warm-up consisted of predetermined dynamic movements completed in 20- yard increments. Speed and power output were assessed by three different means: the 20- yard dash (yards/sec), broad jump (m), and the portable CP. Subjects were given 30 seconds rest in between trials and 1 min between tests. This provided an individualized baseline for the second day of testing. For week 2, group 1 (n=9) completed the same warm-ups but used a weighted vest as a form of resistance (w=20lbs). The subjects then proceeded to complete the speed and power assessments. Group 2 (n=5) went through the same protocol as the week prior (no resistance). RESULTS: Statistical analysis of the data was carried out using SPSS v. 25. A 3-way ANOVA was taken comparing the resistance-based warm-up vs. the control for all three modalities. Power output from the portable CP was the only modality that showed statistical significance (p=0.034). There was no significance in reduced sprint times (p=0.955) and resistance-based warm-ups (20 lbs); nor was there significance between the altered warm-ups and the broad jump (p=0.496). CONCLUSION: The results indicate that in a power-based movement, like a portable CP, may benefit the athlete to participate in resistance based dynamic warm-ups to the similar movement pattern of their specific sport or activity.

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Poster created for the HAS494 Biokinetics Research course and presented at the American College of Sports Medicine (ACSM) Conference