Table 4. Electromyographic activities of the erector spinae with and without pelvic compression belt during maximal isometric PHE-KE and PHE-KF (n=15)

Position	Without PCBs	With PCBs	Within-posture difference (99% CI)	Between-posture difference (99% CI)	p-value
PHE-KE	68.45±3.43	66.87±3.51	−1.57 (−1.34, −1.81)	1.23 (−4.10, 6.57)	>0.05
PHE-KF	66.19±4.10	70.23±3.73	4.04 (5.13, 2.95)

Values are means±SD.
p<0.05.
Abbreviations: CI, confidence interval; PCBs, pelvic compression belts; PHE-KE, prone hip extension with knee extension; PHE-KF, prone hip extension with knee flexion.