Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Stand with dumbbells at sides, feet shoulder-width apart, palms facing forward. Shoulders back, elbows pinned to your ribs. Avoid shrugging, leaning, or pre-curling. Fully extend arms at the bottom. Curl to a point where forearms are parallel to the floor (halfway). Pause briefly, maintaining upright posture and elbow position. Lower slowly (2-3 seconds) to full arm extension. Reset and repeat. Beginners: 3 sets of 10-15 reps with lighter weight.
Maintain parallel as the upper limit; avoid exceeding it. Ensure full arm extension at the bottom of each rep. Use a lighter weight than you would for a full range curl. Keep elbows directly under shoulders throughout the exercise; correct forward drift immediately.
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