Table 1_Neuromuscular control strategies during the Tai Chi heel-kick movement across different levels of motor experience.docx

The participant-level mean number of muscle synergies did not differ significantly between the Master-level and first-class groups (3.73 ± 0.37 vs. 3.63 ± 0.33, p = 0.499). Three representative group-level synergy modules were identified in both groups, with module-specific differences in muscle-weighting composition. The CoA of matched M1 occurred significantly earlier in the Master-level group than in the first-class group (p = 0.004), whereas the CoA of M2 and M3 and the FWHM of all three modules did not differ significantly between groups.

None of the four lower-limb co-contraction indices differed significantly between groups. Phase-level coordination analysis showed a more in-phase but more variable supporting-limb hip–knee pattern during push-off and a more in-phase and less variable kicking-limb hip–knee pattern during recovery in the Master-level group.</p>Conclusion<p>Greater motor experience was associated with selective and phase-specific differences in neuromuscular organization rather than with a general reduction in synergy number or co-contraction.

The findings were characterized primarily by module-specific activation timing and phase-dependent hip–knee coordination.</p>