Each joint action, with the role and emphasis the graph assigns each muscle. These are qualitative anatomical labels, not measured muscle activation.
Hip extensionprimary action
Gluteus maximus (prime mover, high emphasis); Biceps femoris long head (prime mover, high emphasis); Semimembranosus (synergist, high emphasis); Semitendinosus (synergist, moderate emphasis); Adductor magnus (synergist, moderate emphasis)
Spine extensionsecondary action
Erector spinae (stabilizer, high emphasis); Multifidus (stabilizer, moderate emphasis); Quadratus lumborum (stabilizer, moderate emphasis); Transverse abdominis (stabilizer, moderate emphasis); Rectus abdominis (stabilizer, moderate emphasis)
Shoulder flexionsecondary action
Anterior deltoid (synergist, low emphasis); Pectoralis major (synergist, low emphasis); Supraspinatus (stabilizer, low emphasis)
Spine rotationsecondary action · resisted
External oblique (stabilizer, moderate emphasis); Internal oblique (stabilizer, moderate emphasis); Erector spinae (stabilizer, moderate emphasis)