Table 4.

Linear mixed effects models from EMG analyses

Muscle	Parameter	Estimate	SE	t value	P value
Tibialis anterior (%walking)	(Intercept)	3.742	6.717	0.557	0.580
	Ground 1	1.192	8.944	0.133	0.895
	Ground 2	6.193	9.185	0.674	0.504
	Assisted Squat	4.218	9.470	0.445	0.659
	Squat	33.239	9.812	3.388	0.002
Left soleus (%walking)	(Intercept)	4.943	2.783	1.777	0.084
	Ground 1	3.403	3.320	1.025	0.311
	Ground 2	4.659	3.418	1.363	0.180
	Assisted Squat	10.883	3.554	3.062	0.004
	Squat	8.395	3.320	2.529	0.015
Right soleus (%walking)	(Intercept)	5.754	2.411	2.387	0.025
	Ground 1	1.578	2.607	0.605	0.549
	Ground 2	2.914	2.698	1.080	0.287
	Assisted Squat	10.831	2.716	3.988	3.22E-04
	Squat	15.086	3.619	4.168	1.87E-04
Left vastus lateralis (%walking)	(Intercept)	5.927	3.768	1.573	0.123
	Ground 1	−0.155	5.026	−0.031	0.976
	Ground 2	2.174	5.166	0.421	0.676
	Assisted Squat	0.822	5.353	0.153	0.879
	Squat	14.616	5.026	2.908	0.006
Right vastus lateralis (%walking)	(Intercept)	10.508	8.026	1.309	0.198
	Ground 1	0.485	10.407	0.047	0.963
	Ground 2	3.407	10.704	0.318	0.752
	Assisted Squat	2.656	11.104	0.239	0.812
	Squat	29.800	10.407	2.863	0.007

Statistics for parameters are provided relative to values for chair sitting. EMG values included in models were average muscle activity in a given posture normalized to average muscle activity during walking.