Table 2.
Relationship between the number of synergies and the global and local VAF.
| Number of synergies = 2 | Number of synergies = 3 | ||
|---|---|---|---|
| Global VAF (%) | 92.0 ± 8.8 | 92.0 ± 0.9 | |
| Local VAF (%) | RA | 74.9 ± 17.7 | 83.8 ± 13.4 |
| IO | 75.6 ± 19.2 | 84.7 ± 15.9 | |
| RF | 87.0 ± 12.1 | 96.4 ± 6.1 | |
| ES | 66.6 ± 23.4 | 94.6 ± 7.2 | |
| MF | 82.3 ± 18.6 | 95.8 ± 3.4 | |
| TA | 72.0 ± 22.4 | 96.0 ± 3.2 | |
| BF | 75.0 ± 23.9 | 93.6 ± 7.4 | |
| GS | 73.2 ± 20.7 | 96.4 ± 3.0 |
The number of synergies was set as the lowest number at which the global VAF exceeded 90% and the local VAF exceeded 75%. When the number of synergies were 3, the global VAF exceeded 90%, and the local VAF exceeded 75% for all muscles, so it was determined that there were three synergies during the UUS. BF, biceps femoris; ES, erector spinae; GS, gastrocnemius; IO, internal oblique; MF, multifidus; RA, rectus abdominis; RF, rectus femoris; TA, tibialis anterior; VAF, variance accounted for.