Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Set up a decline bench at a 30-45 degree angle. Secure your feet and sit on the bench. Hold a weight plate or dumbbell against your chest. Lie back until your upper body is parallel to the bench, knees slightly bent. Engage your core and lift your upper body towards your knees, controlled. Pause at the top, contracting your abs. Slowly lower back down, avoiding excessive arching. Repeat.
Select a challenging weight with good form. Focus on abdominal engagement, not neck or arm pulling. Exhale during the crunch, inhale on the descent. Maintain slow, controlled movements. Avoid momentum. Keep your spine neutral.
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