Table 2.

Mean across subjects correlation coefficient r values between EMG measurements and (i) muscular activations from SynO, (ii) muscular activations from NMF with SO, for n synergies (n = 2 through 6) of the five subjects (r < 0.4, in red, is considered poor, and r ≥ 0.6, in green, is considered good).

	Pearson correlation coefficient r between across-subject mean EMG vs. muscle activations
	Two synergies		Three synergies		Four synergies		Five synergies		Six synergies		SO
	SynO	SO-NMF	SynO	SO-NMF	SynO	SO-NMF	SynO	SO-NMF	SynO	SO-NMF
R. tibialis anterior	0.58	0.52	0.59	0.75	0.56	0.75	0.56	0.74	0.69	0.76	0.69
R. vastus medialis	0.84	0.74	0.61	0.84	0.68	0.74	0.68	0.75	0.73	0.76	0.71
R. rectus femoris	0.53	−0.07	0.52	−0.09	0.25	−0.02	0.08	−0.06	0.16	−0.05	−0.04
R. vastus lateralis	0.72	0.74	0.75	0.82	0.65	0.80	0.54	0.78	0.73	0.79	0.74
R. adductor magnus middle	0.48	0.54	0.43	0.71	0.52	0.51	0.57	0.56	0.57	0.56	0.52
R. gastrocnemius medial	0.72	0.80	0.87	0.71	0.77	0.67	0.70	0.69	0.75	0.67	0.60
R. gastrocnemius lateral	0.57	0.72	0.76	0.77	0.67	0.66	0.70	0.70	0.64	0.71	0.57
R. semitendinosus	0.36	0.73	0.58	0.89	0.53	0.66	0.66	0.67	0.50	0.60	0.57
R. biceps femoris long head	0.72	0.69	0.57	0.85	0.51	0.79	0.50	0.80	0.54	0.86	0.84
R. gluteus maximus middle	0.74	0.71	0.71	0.86	0.71	0.90	0.84	0.92	0.87	0.92	0.91
R. gluteus medius middle	0.25	0.39	0.45	0.41	0.36	0.40	0.48	0.42	0.38	0.43	0.44
Mean	0.59	0.60	0.62	0.68	0.56	0.62	0.57	0.64	0.59	0.64	0.60