Non-linear dose response effect of cathodal transcranial direct current stimulation on muscle strength in young healthy adults: a randomized controlled study

Table 2 Percentage changes from baseline of the upper extremity muscle strength on the dominant limb are presented as mean (SD) at posttest (POST) in each group

Muscles of the dominant limb	Groups	Percentage change from baseline	Within group comparison			Between group comparison
		POST [Mean (SD)]	Z	p value	Effect size	Overall	Post hoc
		POST [Mean (SD)]	Z	p value	Effect size	Overall	Comparison groups	p value
Elbow flexor	Sham tDCS	− 0.36 (3.04)	− 1.334	0.204	0.39	0.002**	Sham versus 1 mA	0.013*
	1.0 mA ctDCS	− 9.94 (7.27)	− 3.059	< 0.001***	0.88		Sham versus 1.5 mA	0.034*
	1.5 mA ctDCS	− 9.42 (7.11)	− 3.059	< 0.001***	0.88		Sham versus 2 mA	0.972
	2.0 mA ctDCS	0.15 (10.52)	0.392	0.733	0.11		1 mA versus 1.5 mA	0.989
							1 mA versus 2 mA	0.047*
							1.5 mA versus 2 mA	0.104
Elbow extensor	Sham tDCS	1.21 (3.55)	0.471	0.677	0.14	< 0.001***	Sham versus 1 mA	0.037*
	1.0 mA ctDCS	− 10.17 (10.56)	− 2.432	0.012*	0.70		Sham versus 1.5 mA	0.009**
	1.5 mA ctDCS	− 10.75 (5.44)	− 3.059	< 0.001***	0.88		Sham versus 2 mA	0.996
	2.0 mA ctDCS	2.96 (7.59)	0.706	0.519	0.20		1 mA versus 1.5 mA	0.966
							1 mA versus 2 mA	0.019*
							1.5 mA versus 2 mA	0.004**
Wrist extensor	Sham tDCS	0.62 (5.14)	− 0.471	0.677	0.14	< 0.001***	Sham versus 1 mA	0.006**
	1.0 mA ctDCS	− 11.49 (8.03)	− 3.059	< 0.001***	0.88		Sham versus 1.5 mA	0.048*
	1.5 mA ctDCS	− 8.79 (9.44)	− 2.432	0.012*	0.70		Sham versus 2 mA	0.999
	2.0 mA ctDCS	− 0.92 (7.01)	− 0.196	0.850	0.06		1 mA versus 1.5 mA	0.897
							1 mA versus 2 mA	0.010*
							1.5 mA versus 2 mA	0.072

ISSN: 2052-1847