Table 2.

Muscle activity (sEMG).

			ST (%)	DT (%)	Main effects	Interaction effects
D	Exo	No fatigue	14.9 ± 10.2	14.0 ± 9.5	ST–DT F (1, 8) = 8.672, p = 0.019, η p2 = 0.520 Exo F (1, 8) = 4.849, p = 0.059, η p2 = 0.377 Fatigue F (1, 8) = 0.398, p = 0.546, η p2 = 0.047	Task × Exo F (1, 8) = 0.003, p = 0.958, η p2 < 0.001 Task × Fatigue F (1, 8) = 1.296, p = 0.288, η p2 = 0.139 Exo × Fatigue F (1, 8) = 0.109, p = 0.750, η p2 = 0.013 Task × Exo × Fatigue F (1, 8) = 0.573, p = 0.470, η p2 = 0.067
		Fatigue	16.2 ± 7.0	14.7 ± 7.1
	No exo	No fatigue	18.8 ± 13.8	18.5 ± 13.1
		Fatigue	21.4 ± 11.8	19.2 ± 11.4
T	Exo	No fatigue	23.4 ± 22.8	22.5 ± 25.6	ST–DT F (1, 8) = 17.268, p = 0.003, η p2 = 0.683 Exo F (1, 8) = 1.537, p = 0.250, η p2 = 0.161 Fatigue F (1, 8) = 1.226, p = 0.300, η p2 = 0.133	Task × Exo F (1, 8) = 3.050, p = 0.119, η p2 = 0.276 Task × Fatigue F (1, 8) = 0.957, p = 0.357, η p2 = 0.107 Exo × Fatigue F (1, 8) = 0.961, p = 0.356, η p2 = 0.107 Task × Exo × Fatigue F (1, 8) = 0.853, p = 0.383, η p2 = 0.096
		Fatigue	22.1 ± 17.1	22.1 ± 19.2
	No exo	No fatigue	47.5 ± 57.4	23.7 ± 25.3
		Fatigue	26.4 ± 28.4	36.3 ± 45.7
ES	Exo	No fatigue	20.6 ± 34.7	15.2 ± 21.0	ST–DT F (1, 8) = 1.574, p = 0.245, η p2 = 0.164 Exo F (1, 8) = 0.666, p = 0.438, η p2 = 0.077 Fatigue F (1, 8) = 1.168, p = 0.311, η p2 = 0.127	Task × Exo F (1, 8) = 0.528, p = 0.488, η p2 = 0.062 Task × Fatigue F (1, 8) = 0.969, p = 0.354, η p2 = 0.108 Exo × Fatigue F (1, 8) = 0.411, p = 0.539, η p2 = 0.049 Task × Exo × Fatigue F (1, 8) = 1.315, p = 0.285, η p2 = 0.141
		Fatigue	12.8 ± 10.6	11.0 ± 7.3
	No exo	No fatigue	19.2 ± 30.9	15.6 ± 22.7
		Fatigue	16.6 ± 21.1	12.1 ± 12.8

D = M. deltoideus, T = M. trapezius, ES = M. erector spinae, ST = single task, DT = dual task, task = ST and DT, exo = exoskeleton.