Set-up: Grasp a pair of dumbbells with an underhand grip. Set the feet at roughly shoulder width, with a slight bend in the knees. Brace through the core and establish a neutral spine posture.
Lift: Curl the weights up to your chest maintaining the underhand grip, keeping your elbows at your side and eyes straight ahead. At the top of the movement turn the wrists until the hands are in an overhand, palms-down, position, and lower the weight back to the starting position.
Emphasis: Do not swing - keep your core tight and a neutral spine.