Affiliations: [a] College of Physical Education, Universidade de Brasília, Brasília, DF, Brazil | [b] School of Physical Therapy, Universidade de Brasília, Campus UnB Ceilândia, Brasília, DF, Brazil | [c] School of Physical Therapy, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, Brazil
Correspondence:
[*]
Corresponding author: Rodrigo Luiz Carregaro, Campus UnB Ceilândia, Universidade de Brasília, Centro Metropolitano, Conjunto A, lote 01. CEP: 72220-900 - Brasília, DF, Brazil. Tel.: +55 61 3107 8400; Fax: +55 61 3107 8400; E-mail: rodrigocarregaro@unb.br
Abstract: BACKGROUND: Studies have shown that reciprocal exercise using a pre-activation of antagonist muscles may increase the agonist neuromuscular performance.
OBJECTIVE: To compare the efficiency of two modalities of
resistance training (with and without antagonist muscle pre-activation)
during a six week program on knee extension neuromuscular performance of
healthy men.
METHODS: Forty-nine men were randomly assigned into two groups: 1)
reciprocal training: REC - one concentric knee flexion immediately followed
by one concentric knee extension, and 2) control: CON - one concentric knee
extension exercise, without pre-activation. Both training modes were
characterized by three sets of 10 repetitions at 60°/s, 2
days/week. Knee extensor peak moment (PM), load range (LR),
electromyographic activity (EMG) of the vastus medialis (VM), rectus femoris
(RF), and biceps femoris (BF) co-activation were assessed pre and post 6
weeks of training. A 2 × 2 mixed factor ANOVA was applied to evaluate
differences between variables.
RESULTS: Significant increases were found for PM between pre and
post-evaluations for both groups. In relation to VM and RF activation,
co-activation (BF/VM and BF/RF) and LR, no significant differences between
groups and moments were found.
CONCLUSION: In view of the results further research is indicated in
order to examine the utility of longer programs in positively affecting
antagonist muscle co-activation as well as in elucidating its clinical
effects in individuals with musculoskeletal dysfunction.
