Table 2. Comparison of muscle activity of SA and PM depending on the posture during shoulder-strengthening exercise

Muscle	Mean±SD (%MVIC)			F value	p value
	Side-lying	Standing	Supine
SA	83.17±9.23	75.25±14.02	71.95±16.52	6.59	0.002*
PM	71.20±16.65	86.69±11.11	79.85±14.40	9.19	0.001*

SA, serratus anterior; PM, pectoralis major; SD, standard deviation; MVIC, maximal voluntary isometric contraction.
p<0.05.