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

ObjectivesTo 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 designComparative study by repeated measures.SettingYonsei University laboratory.ParticipantsIn total, 15 healthy male subjects participated.Main outcome measuresThe 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.ResultsThe 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).ConclusionsKnee push-up plus exercise on an oscillating unstable surface activates the SA more than the same exercise on static stable and static unstable surfaces.