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  7. Lying Arm Crossover

Exercise guide

Lying Arm Crossover

  • Beginner
  • Compound
  • Rep-based
  • Chest
  • Shoulders
  • Upper arms
  • Waist

The Lying Arm Crossover is a bodyweight isolation exercise that targets the pectoral muscles by emphasizing horizontal adduction and the peak contraction at the midline. It is highly effective for developing the mind-muscle connection and improving chest activation without the need for equipment.

Reviewed by the Crucible team · Updated June 2026

Watch the Lying Arm Crossover demonstrationGuided video and your full workout live in the Crucible app.

Muscles worked

Primary

  • Pectorals

Secondary

  • Abs
  • Obliques
  • Serratus anterior

Equipment

  • Body weight

Setup

  1. Lie flat on your back on a mat or floor with your knees bent and feet flat for stability.
  2. Extend your arms straight out to the sides at shoulder level, palms facing upward.
  3. Retract your shoulder blades slightly, pressing them into the floor to create a stable base for the chest.

How to do it

  1. Exhale as you slowly bring your hands together over the center of your chest in a wide arc, keeping a very slight bend in your elbows.
  2. Cross one hand over the other at the top of the movement, squeezing your pectoral muscles intensely for a two-second count.
  3. Inhale as you slowly lower your arms back to the starting position in a controlled 3-second tempo until you feel a light stretch.
  4. Repeat the movement, alternating which hand crosses on top for each repetition.

Form checklist

  • Keep your lower back pressed firmly against the floor throughout the entire set.
  • Focus on bringing your biceps together rather than just touching your hands.
  • Maintain a consistent, slight bend in the elbows to protect the joints.
  • Avoid using momentum; the movement should be slow and deliberate.

Pro tips

  • To maximize fiber recruitment, imagine you are trying to crush a grape in your armpit as you bring your arms together.
  • Focus on the 'inner' chest by emphasizing the crossover squeeze, ensuring you feel the tension across the sternum.

Make it harder

  • Slow down the eccentric (lowering) phase to 5 seconds to increase time under tension.
  • Hold the peak crossover contraction for 5-10 seconds on the final rep of each set.

Frequently asked

What muscles does the lying arm crossover work?
The lying arm crossover primarily targets the pectorals, and also works the abs, obliques, and serratus anterior as secondary muscles.
What equipment do you need for the lying arm crossover?
The lying arm crossover requires no equipment — just your body weight.
Is the lying arm crossover good for beginners?
Yes. The lying arm crossover is a beginner-friendly movement and a strong foundation to build on.

Related exercises

  • Air Punches MarchBeginner · calves, pectorals, and quadriceps
  • Alternate Front Kick In Place With Arm CirclesBeginner · abs, calves, deltoids, and pectorals
  • Archer Push-UpAdvanced · pectorals
  • Aztec Push UpIntermediate · pectorals, serratus anterior, and triceps

Train this with a plan, not guesswork

Crucible builds the lying arm crossover into a precise program around your body, equipment, location, and time.

Download on the App Store