The vast majority of theses in this collection are open access and freely available. There are a small number of theses that have access restricted to the WWU campus. For off-campus access to a thesis labeled "Campus Only Access," please log in here with your WWU universal ID, or talk to your librarian about requesting the restricted thesis through interlibrary loan.
Date Permissions Signed
Date of Award
Master of Science (MS)
Health and Human Development
Suprak, David N. (David Nathan)
Brilla, Lorraine R., 1955-
Chalmers, Gordon R.
This study compared the effects of two conditioning exercise types on subsequent countermovement jump performance. Fifteen male collegiate rugby players (age 21.1 ± 2.3) completed two experimental protocols in a randomized order. The first protocol consisted of 3 sets of a 5 second maximal isometric half squat (ISO), with 1 minute rest intervals between sets. The second protocol consisted of 2 sets of 5 depth jumps (DJ) at a platform height which was determined by the athletes’ reactive strength index (RSI). These methods were each adapted from prior literature where post-activation potentiation (PAP) was achieved, in order to determine the relative timing and amplitude of the effect using a repeated measures design. Results of a two-way ANOVA for CMJ height reveal a significant main effect of time ((F[5,60] = 8.291, p < 0.001, η² = 0.409), and pairwise comparisons reveal a significant increase in CMJ height at 4-minutes compared to baseline (3.4 ± 0.9%, p = 0.044), as well as a significant decline in CMJ performance from 4-minutes to both 8-minutes (-7.7 ± 3.3%, p = 0.001), and 10-minutes (-4.7 ± 0.7%, p = 0.005). No significant interactions or main effects were found for CMJ height or other performance indices. Potentiating via the DJ or ISO protocols lent no significant difference in CMJ variables, therefore practitioners may use either protocol to enhance jumping performance in their athletes.
Countermovement vertical jump, maximal voluntary isometric contraction, ballistic exercise, complex training
Western Washington University
Subject – LCSH
Exercise--Physiological aspects; Interval training--Physiological aspects; Rest--Physiological aspects; Biomechanics; Human mechanics
Copying of this document in whole or in part is allowable only for scholarly purposes. It is understood, however, that any copying or publication of this thesis for commercial purposes, or for financial gain, shall not be allowed without the author's written permission.
Grey, Alexander I., "A Comparison of the Effect of Conditioning Activity Type on Post-activation Potentiation" (2018). WWU Graduate School Collection. 796.