title: Post vibratory effects on fractionated reaction time and maximum isometric strength.
abstract: Knee and ankle extension isometric strength and reaction time under resisted and unresisted conditions were examined before and after 100 seconds of vibration. Subjects included 10 low strength distance runners and 9 high strength power athletes. The reaction time measures were fractionated into premotor time, corresponding to nervous system processing time, and motor time, corresponding to muscle contraction time. Vibration resulted in no significant change in ankle or knee extension strength or in any ankle extension reaction time component. For knee extension, however, a significant lengthening in unresisted motor was found after vibration. Initial strength level of the subjects was not a factor since the two groups responded to vibration in the same manner for all criterion measures. The results of the present study do not support the use of the post vibratory period for therapeutic purposes.
mesh_terms: D000328:Adult; D006801:Humans; D009119:Muscle Contraction; D011930:Reaction Time; D014732:Vibration