title: The acute effect of a plyometric stimulus on jump performance in professional rugby players.
abstract: Post-activation potentiation (PAP) is the elevation of motor performance to a higher level in response to a conditioning stimulus. Extensive research exists examining the PAP effect after a heavy resistance exercise. However, there is limited research examining the PAP effect after a plyometric stimulus. This study was designed to examine whether a plyometric stimulus could produce a PAP effect comparable to that typically reported with a heavy resistance protocol. Importantly, it was hypothesized that the PAP effect would exist without the same levels of acute fatigue resulting from a heavy stimulus, thus allowing improvement in performance within a short rest interval range. Twenty professional rugby players were recruited for the study. Subjects performed 2 countermovement jumps (CMJs) at baseline and at 1, 3, and 5 minutes after a plyometric stimulus consisting of 40 jumps. Two separate 1-way repeated-measures analyses of variance were conducted to compare the dependent variables CMJ height and peak force at the 4 time points. Results of the Bonferroni adjusted pairwise comparisons indicated that jump height and peak force before plyometric exercises were significantly lower than all other time points (p < 0.01). The main finding of this study indicates that a series of plyometric exercises causes a significant acute enhancement in CMJ height (p < 0.01) and peak force (p < 0.01) throughout the rest interval range of 1-5 minutes. The plyometric series induced an improvement in CMJ height comparable to that reported elsewhere after a heavy lifting stimulus but without the need for a prolonged rest interval. Performing repeated series of plyometric jumps appears to be an efficient method of taking advantage of the PAP phenomenon, thus possibly eliminating the need for a complex training protocol.
authors.affiliation: 1School of Public Health, Physiotherapy and Population Science University College Dublin, Dublin, Ireland; 2Leinster Rugby branch of Irish Rugby Football Union, Dublin, Ireland; and 3Institute for Sport and Health, University College Dublin, Dublin, Ireland.
authors.forename: Daniel P
authors.initials: DP
authors.lastname: Tobin
authors.forename: Eamonn
authors.initials: E
authors.lastname: Delahunt
mesh_terms: D000328:Adult; D054874:Athletic Performance / Q000502:physiology*; D005538:Football / Q000502:physiology*; D006801:Humans; D009068:Movement / Q000502:physiology*; D053580:Muscle Strength; D018482:Muscle, Skeletal / Q000502:physiology*; D064797:Physical Conditioning, Human / Q000502:physiology; D059385:Plyometric Exercise; D012146:Rest / Q000502:physiology; D013997:Time Factors; D055815:Young Adult