Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Place your hands shoulder-width apart with your arms fully locked. Protract and depress your shoulders, lean forward until your feet become light, then tuck your knees toward your chest and lift them off the ground. Hold the position with a tight core and controlled breathing, then lower your feet slowly.
Keep your elbows fully locked throughout the hold. Push your shoulders forward and down to maintain scapular protraction. Lean farther forward rather than trying to lift your feet first. Keep your knees close to your chest and your core braced. Lower out of the position under control to protect your wrists and shoulders.
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