Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Begin by standing with your feet about shoulder-width apart, holding a dumbbell in each hand with your palms facing forward. Initiate the exercise with your arms bent at a 90-degree angle and kept near your torso. Lift the weights by flexing your biceps, fully contracting the muscles at the peak of the movement. Slowly return to the initial position, keeping tension in your arm muscles and preventing your arms from fully straightening.
Keep your elbows relatively still and close to your body during the entire exercise. Focus on maintaining a straight posture and bracing your abdominal muscles. Really contract your biceps as you lift the weights to maximize muscle engagement. Be sure to actively involve your forearms and keep your wrists in a neutral position. Control the weight as you lower it to maintain consistent tension. Avoid letting your arms fully extend at the bottom of the movement.
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