Serratus anterior muscle activation during knee push-up plus exercise performed on static stable, static unstable, and oscillating unstable surfaces in healthy subjects.

OBJECTIVES

To compare electromyographic (EMG) activity of the serratus anterior (SA) during knee push-up plus exercises according to various surfaces (static stable, static unstable, and oscillating unstable surfaces).

STUDY DESIGN

Comparative study by repeated measures.

SETTING

Yonsei University laboratory.

PARTICIPANTS

In total, 15 healthy male subjects participated.

MAIN OUTCOME MEASURES

The subjects performed knee push-up plus exercises on three different surfaces: static stable, static unstable, and oscillating unstable surfaces. Surface EMG activity of the SA for the peak and average amplitudes were collected from the dominant arm and presented as a percentage of the maximal voluntary contraction. A one-way repeated-measures ANOVA with a Bonferroni post hoc test was performed to compare differences in SA EMG activity according to the surface.

RESULTS

The peak and average amplitudes of SA activity were significantly greater during knee push-up plus on the oscillating unstable surface than on the static stable or static unstable surfaces (p < 0.01). Additionally, there was no significant difference between the stable and static unstable surfaces (p > 0.05).

CONCLUSIONS

Knee push-up plus exercise on an oscillating unstable surface activates the SA more than the same exercise on static stable and static unstable surfaces.