Table 2.

Intra-subject consistency of muscle weights and activation signals across subgroups of gait cycles, principal muscles recruited, and biomechanical functions of the subject-specific muscle synergies.

Subject	Consistency of motor functions		Principal muscles	Biomechanical function
	Muscle weights CS (mean ± SD)	Activation signals CC (mean ± SD)
Subject #1	–	–	–	–
Subject #2	0.50 ± 0.22	0.80 ± 0.09	VM-RF	Stiff the knee at heel strike and the load acceptance phase
Subject #3	–	–	–	–
Subject #4	0.83 ± 0.08	0.91 ± 0.05	GMD-LGS-SOL	Stabilize hip joint and the foot at the heel strike
Subject #5	0.97 ± 0.01	0.99 ± 0.004	PL	Not defined
Subject #6	0.98 ± 0.03	0.99 ± 0.004	TFL-RF	Stabilize hip joint during swing
	0.74 ± 0.25	0.80 ± 0.17	VM	Not defined
Subject #7	0.49 ± 0.16	0.56 ± 0.09	GMD	Control the hip joint at heel strike and the end of the swing
Subject #8	0.99 ± 0.004	0.99 ± 0.004	VM-GMD-RF	Stiff the knee and control the hip joint at heel strike and the end of the swing
Subject #9	–	–	–	–
Subject #10	0.70 ± 0.17	0.87 ± 0.11	VM	Stiff the knee at heel strike and the end of the swing
Subject #11	0.96 ± 0.02	0.98 ± 0.01	VM-GMD	Stiff the knee and control the hip joint at heel strike and the end of the swing
Subject #12	0.97 ± 0.02	0.99 ± 0.01	VM-GMD	Stiff the knee and control the hip joint at heel strike and the end of the swing

Subjects #1, #3, and #9 showed no subject-specific synergies, but only shared synergies.