Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Lie on your side, knees bent and stacked. Support yourself with your bottom arm and place your top hand behind your head. Engage your core, lift your upper body towards your hip, contracting your obliques. Hold briefly, then slowly lower back down. Repeat on both sides.
Engage obliques to lift, avoiding neck/shoulder strain. Control movements, avoid momentum. Exhale during the crunch, inhale on the descent. Maintain a neutral neck position. Perform slowly for maximum muscle tension.
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