Left and right transversus abdominis (TrA) length and thickness and multifidus (MF) anteroposterior (AP) and mediolateral (ML) thickness during rest and contraction in men (n=18) and women (n=12)
| Parameter | Rest, mm | Contract, mm | ||
| Left | Right | Left | Right | |
| Men (n=18) | ||||
| TrA length | 66.7 (17.8) | 69.3 (15.2) | 57.2 (18.3) | 60.1 (18.6) |
| TrA thickness | 9.1 (3.3) | 8.0 (1.6) | 7.7 (2.1) | 8.3 (1.6) |
| MF AP thickness | 29.4 (3.5) | 29.0 (3.6) | 31.4 (3.7) | 31.0 (3.7) |
| MF ML thickness | 25.0 (3.3) | 24.8 (2.7) | 16.3 (2.2) | 24.3 (2.6)‡ |
| Women (n=12) | ||||
| TrA length | 51.9 (11.5) | 53.8 (14.2) | 39.6 (8.8) | 42.5 (9.5) |
| TrA thickness | 6.1 (1.7) | 7.7 (1.6)* | 6.8 (1.7) | 7.5 (2.1) |
| MF AP thickness | 24.5 (3.0) | 24.6 (3.0) | 25.5 (3.3) | 25.9 (3.3) |
| MF ML thickness | 23.1 (2.3) | 22.9 (2.8) | 14.3 (1.5) | 22.7 (2.3)‡ |
Data are mean(SD).
*P<0.05.
†P<0.001 when compared with left side. All measurements are averaged over all lumbar levels.