Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Stand with feet shoulder-width apart, holding a kettlebell in each hand (underhand grip). Keep elbows close to your torso, palms forward. Exhale, curl kettlebells up by bending elbows to shoulder level, contracting biceps. Pause, then inhale as you slowly lower to the start.
Maintain a straight posture. Squeeze biceps at the top. Control the lowering phase. Avoid swinging; isolate arm movement. Start with a lighter weight to ensure proper form.
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