Muscles worked
The Arnold press, named after Arnold Schwarzenegger, is a shoulder press with a twist. Your front delts do most of the work, with help from your side delts and triceps. Because you start with your elbows in front of your body, your front delts and upper chest get extra work in the lower part of the movement. The twist is often said to give the side delts more work, but the difference from a regular shoulder press is probably small. Most people use slightly lighter dumbbells here than in a regular seated press.
Common mistakes
- Leaning back when it gets heavy. If you arch and slide forward on the seat, the exercise becomes more of an incline press for the chest. Keep your back against the backrest and your ribs down, and pick lighter dumbbells if you cannot.
- Your wrists bend back. As the dumbbells turn, it is easy to let the wrist fold. Keep the handle low in your palm, directly above your forearm, throughout the twist.
- Turning around before the dumbbells are down. As you tire, it is tempting to turn around well above your shoulders. You then skip the part of the movement that sets it apart from a regular press. Lower all the way until the dumbbells are in front of your shoulders with your palms facing you.
Variations and alternatives
- The seated dumbbell shoulder press without the twist, when you want to press heavier dumbbells.
- The standing shoulder press makes your abs and legs work harder.
- The machine shoulder press has a fixed path and is easier to take close to your limit.
- Dumbbell lateral raises are a good complement that trains your side delts more directly.
Sets and reps
The Arnold press suits building muscle best, with 8 to 12 reps over three or four sets. For endurance, 12 to 15 reps works well. Heavy sets of 3 to 6 reps are not what it is made for, as the twist gets hard to control with heavy dumbbells. For heavy overhead strength, the overhead press is a better choice. The guide to sets and reps explains more.
Dumbbells often go up in steps of 2 or 2.5 kg, which is a big jump for your shoulders. Apply progressive overload with reps first, and stay with the same pair until you reach the top of your range in every set. Keep one or two reps in reserve, as the twist is the first thing to get sloppy when you tire.