Fig. 4

The number of muscle synergies estimated based on variance-accounted-for (VAF). A-B, The mean and SD of VAF across the participants at each assessment week for the “Habitual” (A, blue) and “As-Trained” conditions (B, red). The number of muscle synergies where the group mean VAF exceeds the VAF threshold at 90% (black line) is highlighted (grey). C, The mean and SD of the number of muscle synergies that can explain at least 90% of the total variance of raw EMGs across the participants