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  5. Chest
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  7. Arm Crossover

Exercise guide

Arm Crossover

  • Intermediate
  • Isolation
  • Rep-based
  • Chest
  • Shoulders

A dynamic movement that improves shoulder mobility while activating the pectoral and deltoid muscles through horizontal adduction. It serves as an excellent warm-up or active recovery exercise to increase blood flow and flexibility in the upper body.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Arm Crossover demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Deltoids
  • Pectorals

Secondary

  • Biceps
  • Triceps

Equipment

  • Body weight

Setup

  1. Stand upright with your feet shoulder-width apart and a neutral spine.
  2. Extend your arms straight out to your sides at shoulder height, palms facing forward.
  3. Engage your core to stabilize your torso and maintain a tall posture.

How to do it

  1. Swing both arms horizontally across the front of your body in a controlled, rhythmic motion.
  2. Cross one arm over the other as far as comfortably possible, exhaling as the arms meet in the center.
  3. Inhale as you swing your arms back to the starting position, opening the chest wide to feel a stretch.
  4. Repeat the movement, alternating which arm crosses on top for each repetition.

Form checklist

  • Keep your arms parallel to the floor throughout the entire movement.
  • Maintain a slight bend in the elbows to protect the joints.
  • Keep your shoulders depressed and away from your ears.
  • Avoid arching your lower back or rotating your torso as you swing.

Pro tips

  • Focus on squeezing your shoulder blades together at the back of the movement to engage the upper back.
  • Imagine you are performing a standing chest fly to increase the mind-muscle connection with the pectorals.
  • Use a controlled tempo rather than relying purely on momentum to ensure the muscles are doing the work.

Make it harder

  • Slow down the tempo significantly to increase time under tension for the deltoids.
  • Hold the 'crossed' position for 2 seconds to maximize the stretch on the posterior deltoids and serratus anterior.

Frequently asked

What muscles does the arm crossover work?
The arm crossover primarily targets the deltoids and pectorals, and also works the biceps and triceps as secondary muscles.
What equipment do you need for the arm crossover?
The arm crossover requires no equipment — just your body weight.
Is the arm crossover good for beginners?
The arm crossover is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.

Related exercises

  • Alternate Front Kick In Place With Arm CirclesBeginner · abs, calves, deltoids, and pectorals
  • Around The World Lying On FloorIntermediate · deltoids and pectorals
  • Barbell Bench Press With 1 BoardIntermediate · deltoids, pectorals, and triceps
  • Barbell Pullover-To-PressIntermediate · deltoids, pectorals, and triceps

Train it with Crucible Fit.

Every movement in this library is in the app with video and instructions, ready for your own sessions on the days between Crucibles. Your first Crucible is on us.

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