The term "biceps curl" refers to any of a number of weight training exercises that primarily targets the biceps brachii muscle. It may be performed using a barbell, dumbbell, resistance band, or other equipment. Overview The biceps curl mainly targets the biceps brachii, brachialis and brachioradialis muscles. The biceps is stronger at elbow flexion when the forearm is supinated (palms turned upward) and weaker when the forearm is pronated. The brachioradialis is at its most effective when the palms are facing inward, and the brachialis is unaffected by forearm rotation. Therefore, the degree of forearm rotation affects the degree of muscle recruitment between the three muscles. Form A biceps curl usually starts with the arm in a fully extended position, holding a weight with a supinated (palms facing up) grip. A full repetition consists of bending or "curling" the elbow until it is fully flexed, then slowly lowering the weight to the starting position. The torso should remain upright instead of swinging back and forth, as doing so transfers the load away from the biceps and onto other muscles, reducing the effectiveness of the exercise. The elbows are also usually kept stationary at the side of the torso, as allowing the elbows to move in front of the weight's center of gravity removes tension on the biceps before full contraction is achieved. To maximize the activation of biceps, conducting this exercise using the full range of motion is generally recommended. But for advanced trainers, they can apply a different variation of range in order to acquire some particular emphasis muscle activation. Some may argue that the tension on muscle is most significant during the mid-range, practice biceps curl with a half range of motion to let muscle generate the most force. The research found that the preacher curl targets the long head of the biceps significantly only when the arm was almost fully extended, and the range of motion was short. On the other hand, the incline dumbbell curl and the regular biceps curl activated the biceps brachii throughout the entire range of motion. They may be more effective in maximizing the biceps activation. Variations Several variations on the biceps curl by using different equipment, forms, and volume. But the general idea is still to target the biceps activation. Below are some typical variations using common equipment that are prevalent among trainers. Dumbbells Dumbbell Incline Curl: With an adjustable bench