Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Stand with feet shoulder-width apart, dumbbells at your sides. Step forward with your right foot, lowering hips until knees are bent at 90 degrees. Front knee over ankle, back knee hovering. Push through your right heel to rise, bringing your left foot forward into the next lunge. Alternate legs.
Maintain upright posture, chest up, shoulders back. Control the descent for muscle engagement. Prevent front knee from extending past toes. Use a mirror to check form. Start with lighter weights.
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