Table 5. Rectus abdominis muscle activity over time in each therapy group (Unit: %RMS).

	Before	2 weeks2	4 weeks3	6 weeks3
Group b	90.5±6.5 a	89.2±6.7	90.3±6.5	90.7±7.8
Group c	89.0±5.8	94.3±6.3***	100.5±6.8†***	111.9±7.3†††***
Group d	91.7±5.5	103.2±9.1††≠***	112.9±9.8†††≠≠***	123.0±8.9†††≠≠***