Table 1. Abdominal muscle activities and pelvic rotation angle during active straight leg raise with and without pelvic floor muscle contraction (PFMC)

Variables	Without PFMC	With PMFC	Mean difference	95% CI	Cohens’ d
Rt. TrA/IO (%MVIC)	27.51±9.95	35.82±9.73*	–8.31±6.14	–11.58 to –5.04	0.844
Lt. TrA/IO (%MVIC)	19.99±12.09	35.51±14.80*	–15.52±16.43	–24.28 to –6.77	1.149
Rt. EO (%MVIC)	23.81±10.70	24.93±11.90	–1.12±6.47	–4.57 to 2.33	0.001
Lt. EO (%MVIC)	35.29±18.02	24.74±14.18*	10.55±11.29	4.53 to 16.57	0.651
Rt. MF (%MVIC)	21.28±5.18	21.67±5.05	–0.39±0.89	–0.86 to 0.08	0.076
Lt. MF (%MVIC)	14.27±4.41	14.85±4.43	–0.58±1.49	–1.38 to 0.21	0.131
Pelvic rotation angle (°)	6.8±2.8	2.5±1.7*	4.32±3.12	2.65 to 5.98	1.905

Data are mean±SD; CI, confidence interval; TrA/IO=transversus/internal oblique abdominis; EO=external oblique abdominis, MF= multifidus;
Paired t test significantly different from pre-testing at p<0.05.