N Bullock
An investigation into the acute effects of depth jumps on maximal strength performance
Bullock, N; Comfort, P
Abstract
Research
has demonstrated that high-load low-velocity (HLLV) exercises
($85% 1 repetition maximum [1RM]) increase performance
in subsequent low-load high-velocity (LLHV)
exercises, when separated by a rest period $4 minutes. To
date, few studies have investigated LLHV exercises on
subsequent HLLV exercises. The purpose of this study was to
compare the effects of 2, 4, or 6 depth jumps (DJs) on
subsequent 1RM back squat performance. Fourteen subjects
(age 22 6 4 years, height 177 6 10 cm, body mass 80.3 6
14.4 kg) completed five 1RM back squat testing sessions,
either control, retest, or 1 of 3 interventions (2, 4, or 6 DJs
from a height of 33 cm, 4 minutes before the first 1RM
attempt), in a counterbalanced order. Intraclass correlation
coefficients demonstrated a high test–retest reliability for the
1RMs (r = 0.989, p , 0.001). Repeated-measures analysis of
variance with Bonferroni post hoc analysis revealed significantly
greater 1RM performance (140.71 6 35.68 kg:
p = 0.004, 140.50 6 33.77 kg: p , 0.001, 141.43 6 34.39 kg:
p = 0.002, respectively) for each intervention (2, 4, or 6
repetitions, respectively) compared to the control condition
(132.43 6 34.56 kg). No significant differences were found
between interventions (p . 0.05). The findings of this
investigation demonstrate that the inclusion of 2, 4, or 6 DJs,
4 minutes before a maximal squat, enhances subsequent
strength performance.
Citation
Bullock, N., & Comfort, P. (2011). An investigation into the acute effects of depth jumps on maximal strength performance. Journal of Strength and Conditioning Research, 25(11), 3137-3141. https://doi.org/10.1519/JSC.0b013e318212e224
| Journal Article Type | Article |
|---|---|
| Publication Date | Nov 1, 2011 |
| Deposit Date | Nov 24, 2011 |
| Journal | Journal of Strength and Conditioning Research |
| Print ISSN | 1064-8011 |
| Publisher | Lippincott, Williams & Wilkins |
| Peer Reviewed | Peer Reviewed |
| Volume | 25 |
| Issue | 11 |
| Pages | 3137-3141 |
| DOI | https://doi.org/10.1519/JSC.0b013e318212e224 |
| Publisher URL | http://dx.doi.org/10.1519/JSC.0b013e318212e224 |