Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Stand with feet hip-width apart, arms extended for balance. Shift weight to one leg, lifting the opposite leg straight. Lower your body into a squat on the standing leg, keeping the lifted leg extended and core engaged. Descend until your thigh is parallel to the ground. Push through the heel of the standing leg to return to the start. Repeat, alternating legs.
Maintain a straight back. Keep your knee aligned with your toes. Use support if needed. Start with a partial range of motion, gradually increasing depth. Warm up beforehand. Incorporate ankle mobility exercises.
MuscleTrain is actively being built. If something looks broken, or you have a suggestion, let us know — it really helps shape the app.