Table 3. Normalized activation of leading arm for upper extremity muscles in two-handed backhand strokes (% MVC).

Leading arm		Drive volley (Mean ± SD)	Groundstroke (Mean ± SD)	p-value	Effect size
Preparation	FCR	18.00 ± 4.54	16.06 ± 5.72	.10	0.38
	ECR	12.09 ± 5.16	11.21 ± 4.87	.28	0.18
	BB	3.98 ± 2.04	3.94 ± 1.52	.93	0.02
	TB	5.54 ± 2.84	5.68 ± 3.37	.84	0.04
Early Acceleration	FCR	52.50 ± 20.52	40.39 ± 13.91	.02*	0.69
	ECR	44.70 ± 31.22	44.50 ± 29.88	.97	0.01
	BB	20.33 ± 16.05	28.98 ± 19.43	.05	0.49
	TB	24.56 ± 13.22	31.52 ± 26.96	.22	0.33
Late Acceleration	FCR	55.90 ± 35.49	48.12 ± 21.30	.15	0.27
	ECR	91.17 ± 36.89	94.66 ± 32.42	.53	0.10
	BB	52.19 ± 18.74	52.14 ± 21.03	.99	0.00
	TB	32.06 ± 13.09	31.30 ± 24.34	.88	0.04
Early Follow-through	FCR	22.53 ± 5.84	19.98 ± 7.91	.14	0.37
	ECR	32.62 ± 17.12	28.86 ± 17.19	.44	0.22
	BB	22.57 ± 13.46	23.49 ± 15.94	.62	0.06
	TB	12.18 ± 3.93	16.95 ± 19.11	.38	0.35
Late Follow-through	FCR	9.69 ± 5.49	10.93 ± 6.35	.24	0.21
	ECR	16.39 ± 12.16	14.33 ± 11.29	.17	0.18
	BB	18.87 ± 8.81	18.67 ± 9.19	.94	0.02
	FCR	18.00 ± 4.54	16.06 ± 5.72	.10	0.38

* p < 0.05