The use of magnetic technology for its proposed therapeutic benefits (e.g. reduce discomfort, reduce stress, and improve health) has become popular in recent years. Some distributors even claim their products may increase strength and power. However, these claims may be scientifically unfounded since many are based on personal testimony rather than scientific evidence. In fact, there is minimal research available assessing the benefits of magnets during exercise. Therefore, the purpose of this study was to examine the effects of magnetic insoles on power output as measured by vertical jump in 15 male collegiate volleyball players (age=19.87±1.64yrs., ht=74.93±5.02 in., wt-84.39±10.83kg.). Subjects arrived at the testing site and were randomly assigned to one of two conditions: Nikken, Inc. MagstridesTM magnetic insoles (mg) and placebo insoles (pl). Study participants and researchers were both blinded to the testing condition. Subjects warmed up on a cycle ergometer for 10 minutes before performing three standing vertical jumps with 20 seconds rest between jumps. Weight, height, standing reach, jump reach (VertecaTM), and vertical jump were recorded. Subjects were then given 15 minutes rest before repeating the process under the other condition. One sample t-tests revealed no differences between conditions in peak vertical jump (p=.60 1; mg=27. 13±2.79 in., pl=26.77±2.65 in.), average vertical jump (p=.920; mg=26.39±2.59 in., pl=26.32±2.52 in.), or peak power output (p=. 872; mg=146.84±20. 11 kg-m/sec, pl=145.98 ±19.43 kgm/sec). From our findings, we conclude that magnetic insoles have no effect on power output as measured by vertical jump in male collegiate volleyball players.