The Arnold press is an upper-body strength exercise that targets the shoulders, chest, and triceps. It is a variation of the traditional dumbbell shoulder press, named after Arnold Schwarzenegger, a well-known bodybuilder who popularized the exercise. The Arnold press involves a wrist rotation movement that ends when your palms face forward at the top of the press. This twist motion adds depth to your range of motion and puts more emphasis on your rear delts, helping you build the strength to draw back your shoulders and stand up straight.

To perform the Arnold press, you need a set of dumbbells and an exercise bench with back support. Here are the steps to perform the Arnold press:

1. Sit on an exercise bench with back support and hold two dumbbells in front of you at about upper chest level with your palms facing your body.
2. Begin the press by lifting the dumbbells up to shoulder level, rotating your palms to face forward as you lift.
3. Continue pressing the dumbbells overhead until your arms are fully extended.
4. Reverse the motion by lowering the dumbbells back down to shoulder level while rotating your palms to face your body.
5. Lower the dumbbells back down to the starting position.

There are several variations of the Arnold press, including the single-arm Arnold press, the alternating Arnold press, and the incline Arnold press. These variations add more challenge to the exercise and engage different muscle groups.