Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Stand with feet shoulder-width apart, dumbbells in each hand, palms facing you. Keep elbows close to your torso. Curl one dumbbell, rotating your wrist upwards as you lift to shoulder level. Squeeze your bicep at the top. Slowly lower back to the starting position, rotating your wrist back to neutral. Alternate arms.
Control the movement, avoid swinging. Squeeze your bicep at the top. Engage your core and maintain a straight back. Use a full range of motion. Start with lighter weights. Exhale on the curl, inhale on the lower.
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