Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Hang from a pull-up bar with an overhand grip, hands shoulder-width apart. Smoothly raise your bent knees to your elbows. Pause for a split second and slowly lower your legs. Repeat for the required number of reps.
Control the movement, don't swing, move slowly. Exhale as you raise your knees, inhale as you lower them. If raising your knees high is hard, start with a smaller range of motion.
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