Table II.

Electromyographic activity of the scapular muscles during spiking (% MVIC, mean ± SD)

Muscle	Phase
	Wind-up	Cocking	Acceleration	Deceleration	Follow-through
Upper trapezius
Standard position	40 ± 34	47 ± 36	56 ± 49	39 ± 23	26 ± 16
Posterior position	52 ± 23	67 ± 51	88 ± 56	41 ± 37	30 ± 18
Medial position	44 ± 19	59 ± 46	61 ± 55	28 ± 27	18 ± 13
Lateral position	40 ± 17	62 ± 81	52 ± 39	41 ± 27	28 ± 17
Middle trapezius
Standard position	28 ± 35	38 ± 49	62 ± 42	25 ± 17	21 ± 19
Posterior position	31 ± 46	33 ± 28	74 ± 48	27 ± 19	18 ± 11
Medial position	26 ± 19	41 ± 37	32 ± 26	17 ± 15	10 ± 7
Lateral position	28 ± 23	49 ± 65	63 ± 19	31 ± 20	21 ± 9
Lower trapezius
Standard position	37 ± 25	52 ± 30	37 ± 27	15 ± 13	11 ± 9
Posterior position	39 ± 23	66 ± 47	52 ± 41	19 ± 18	18 ± 19
Medial position	27 ± 16	50 ± 39	38 ± 34	13 ± 11	8 ± 6
Lateral position	28 ± 18	51 ± 28	53 ± 45	22 ± 26	11 ± 10
Serratus anterior
Standard position	48 ± 51∗	58 ± 47	42 ± 36	43 ± 22	30 ± 22
Posterior position	43 ± 11	55 ± 29	61 ± 51	32 ± 22	31 ± 19
Medial position	17 ± 9	35 ± 48	68 ± 68	54 ± 32	41 ± 29
Lateral position	16 ± 9∗	50 ± 48	36 ± 34	36 ± 25	24 ± 13

MVIC, maximal voluntary isometric contraction; SD, standard deviation.

^∗Significant difference between the standard position and the lateral position (P < .05).