Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Stand tall with your feet hip-width apart. Bend one knee backward and grab that foot with your opposite hand. Lower your body by bending your supporting leg. Once your back knee lightly touches the floor, push yourself back up to the starting position. Switch sides and repeat for the desired number of sets and reps.
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