Two studies were performed to estimate the reliability of the Cybex Reactor in assessing agility tasks. In Study 1, participants (n =13) underwent identical testing sessions twice in 1 week. In Study 2, participants (n = 13) underwent identical testing sessions twice in 1 week, once 3 weeks later, and once 6 weeks later. Testing sessions consisted of four identical agility tasks requiring participants to react to cues shown on a video monitor. In Study 1, intraclass correlation coefficients (ICC) were .47 for Day 1 and .75 for Day 2 for time to complete each task. Participants performed faster on Day 2 (p < .05). In Study 2, ICC ranged from .58 to .83. ICC between sessions ranged from .59 to .73. Participants performed significantly faster each successive session except between Weeks 3 and 6 (p < .05). The Reactor appears to be reliable in assessing agility tasks with test–retest intervals of up to 6 weeks.
All authors are associated with the Athletic Training Research Laboratory at Penn State University, 15 Recreation Building, University Park, PA 16802. Jay Hertel, Sheri A. Hale, Phil D. Johnson, and W.E. Buckley are with the Department of Kinesiology. Craig R. Denegar is with the Departments of Kinesiology and Orthopaedics and Rehabilitation.