Fig 3. Comparison of muscle activity during the exercises for each muscle.

Muscle activity showed the percentage of maximal voluntary contraction (% MVC; mean ± SD). Abbreviations: RA = rectus abdominis; REO = right external oblique; LEO = left external oblique; RIO = right internal oblique; LIO = left internal oblique; Gmed = gluteus medius; ADD = adductor longus. The significant differences between the exercises were listed in Table 1.