Evaluation of plyometric intensity using electromyography.

Full Abstract

The purpose of this study was to investigate the motor unit activation of the quadriceps (Q), hamstring (H), and gastrocnemius (G) muscle groups during a variety of plyometric exercises to further understand the nature of these exercises. Twenty-three athletes volunteered to perform randomly ordered plyometric exercises, thought to cover a continuum of intensity levels, including two-foot ankle hops; 15-cm cone hops; tuck, pike, and box jumps; one- and two-leg vertical jump and reach; squat jumps with approximately 30% of their 1RM squat load; and 30- and 61-cm depth jumps. Integrated electromyographic data were analyzed for each exercise using a one-way repeated-measures ANOVA. Results revealed significant main effects for the Q when all subjects are analyzed, as well as for separate analysis of men, women, subjects with vertical jumps greater than 50 cm, and those with vertical jumps less than or equal to 50 cm (p < or = 0.05). Significant main effects were also found for the G muscle group in the analysis of all subjects, as well as for men and subjects with vertical jumps greater than 50 cm (p < or = 0.05). No significant main effects were found for the H muscle group. Pairwise comparisons revealed a variety of differences among plyometric exercises. In some cases, plyometrics previously reported to be of high intensity, such as the depth jump, yielded relatively little motor unit recruitment compared with exercises typically thought to be of low intensity. Results can assist the practitioner in creating plyometric programs based on the nature of the motor unit recruitment.

Author information

Author/s: Ebben, William P (WP); Simenz, Christopher (C); Jensen, Randall L (RL);

Affiliation: Department of Physical Therapy, Program in Exercise Science, Marquette University, Milwaukee, Wisconsin, USA. webben70(-atsign-)hotmail.com

Journal and publication information

Publication Type: Comparative Study; Journal Article; Randomized Controlled Trial

Journal: Journal of strength and conditioning research / National Strength & Conditioning Association (J Strength Cond Res), published in United States. (Language: eng)

Reference: 2008-May; vol 22 (issue 3) : pp 861-8

Dates: Created 2008/06/06; Completed 2008/08/07;

PMID: 18438229, status: MEDLINE (last retrieval date: 2/18/2009, IMS Date: )

Sourced from the National Library of Medicine. Abstract text and other information may be subject to copyright.

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