title: Effects of plyometrics performed during warm-up on 20 and 40 m sprint performance.
abstract: BACKGROUND
  Postactivation potentiation in the form of a plyometric during warm-ups have been shown to improve performance in some speed/power events. This study aimed to determine if a plyometric during warm up can increase sprint performance in a 20 and 40 m sprint.
  
  
  METHODS
  In this study we measured sprint times of 10 male track and field athletes over distances of 20 and 40 m after warm-ups with and without a plyometric exercise. The subjects performed the sprints at the same time on 2 different days, once with the experimental treatment, a plyometric exercise in the form of a plate jump, and once without. Plate jumps were chosen as the plyometric treatment because they do not require special equipment or facilities. The plate used for the plate jumps had a mass of 11.2 kilograms, which was between 12.8-16.6% of each athlete's body mass.
  
  
  RESULTS
  Statistical analysis showed a decrease in sprint time when a plyometric was performed during the warm-up for both 20 (t-test P<0.05) and 40 m sprints (t-test P<0.01). The effect sizes of the improvement for both the 20 and 40 m sprints were d=0.459 and d=0.405, respectively, which is considered a small to medium effect.
  
  
  CONCLUSIONS
  These results indicate that including a plyometric exercise during warm-ups can improve sprint performance in collegiate aged male sprinters during short sprints.
authors.affiliation: Athletic Department, Michigan State University, Ann Arbor, MI, USA.
authors.forename: Ceith C
authors.initials: CC
authors.lastname: Creekmur
authors.affiliation: Department of Otolaryngology Head and Neck Surgery, Johns Hopkins University, Baltimore, MD, USA.
authors.forename: Joshua L
authors.initials: JL
authors.lastname: Haworth
authors.affiliation: Department of Kinesiology and Health, Miami University, Oxford, OH, USA.
authors.forename: Ronald H
authors.initials: RH
authors.lastname: Cox
authors.affiliation: Department of Kinesiology and Health, Miami University, Oxford, OH, USA - walshms@miamioh.edu.
authors.forename: Mark S
authors.initials: MS
authors.lastname: Walsh
mesh_terms: D056352:Athletes; D054874:Athletic Performance / Q000502:physiology*; D006801:Humans; D008297:Male; D059385:Plyometric Exercise / Q000379:methods*; D011897:Random Allocation; D012420:Running / Q000502:physiology*; D014495:Universities; D063996:Warm-Up Exercise / Q000502:physiology*; D055815:Young Adult