The standing lateral raise primarily works the lateral deltoid muscles, which are the muscles found on the sides of the shoulders. Synergists include the middle and lower trapezius and the anterior, or front, deltoid muscles.
The standing lateral raise involves holding dumbells in both hands in front of the thighs and raising them to the sides until the elbows are at shoulder height. Since it is an isolation exercise, it is important to avoid employing other muscle groups to do the work of driving the weights upward. Another exercise commonly employed to target the lateral deltoid muscles is the upright row.