The Effect of Heavy- vs. Light-Load Jump Squats on the Development of Strength, Power, and Speed
- ASU Author/Contributor (non-ASU co-authors, if there are any, appear on document)
- N. Travis Triplett Ph.D., Professor (Creator)
- Institution
- Appalachian State University (ASU )
- Web Site: https://library.appstate.edu/
Abstract: The purpose of this investigation was to examine the effect
of an 8-week training program with heavy- vs. light-load
jump squats on various physical performance measures and
electromyography (EMG). Twenty-six athletic men with
varying levels of resistance training experience performed
sessions of jump squats with either 30% (JS30, n = 9) or 80%
(JS80, n = 10) of their one repetition maximum in the squat
(1RM) or served as a control (C, n = 7). An agility test, 20-
m sprint, and jump squats with 30% (30J), 55% (55J), and
80% (80J) of their 1RM were performed before and after
training. Peak force, peak velocity (PV), peak power (PP),
jump height, and average EMG (concentric phase) were calculated
for the jumps. There were significant increases in PP
and PV in the 30J, 55J, and 80J for the JS30 group (p <= 0.05).
The JS30 group also significantly increased in the 1RM with
a trend towards improved 20-m sprint times. In contrast, the
JS80 group significantly increased both PF and PP in the 55J
and 80J and significantly increased in the 1RM but ran significantly
slower in the 20-m sprint. In the 30J the JS30
group’s percentage increase in EMG activity was significantly
different from the C group. In the 80J the JS80 group’s
percentage increase in EMG activity was significantly different
from the C group. This investigation indicates that training
with light-load jump squats results in increased movement
velocity capabilities and that velocity-specific changes
in muscle activity may play a key role in this adaptation.
The Effect of Heavy- vs. Light-Load Jump Squats on the Development of Strength, Power, and Speed
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Created on 6/17/2011
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Additional Information
- Publication
- McBride, J.M., Triplett-McBride, T., Davie, A., and Newton, R.U. (2002) The effect of heavy- vs. light-load jump squats on the development of strength, power, and speed. Journal of Strength and Conditioning Research 16(1), 75-82. Published by National Strength and Conditioning Association (ISSN: 1533-4287). Original version available from publisher’s web site: http://www.nsca-lift.org
- Language: English
- Date: 2002