FormTwinExercises › Mountain Climber

What muscles does the Mountain Climber work?

The mountain climber is a dynamic plank variation that trains the core and hip flexors while driving your heart rate up for conditioning.

Primary muscles worked

Secondary muscles worked

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How to do the Mountain Climber

  1. Start in a high plank, hands under shoulders, body in a straight line.
  2. Brace your core and keep your hips level.
  3. Drive one knee toward your chest.
  4. Switch legs quickly, like running in place.
  5. Keep a steady rhythm without bouncing the hips.

Common mistakes

Variations

Frequently asked questions

What muscles do mountain climbers work?

Mountain climbers mainly train the abs and hip flexors as you drive the knees in, while the shoulders and triceps hold the plank and the obliques resist rotation. Cross-body versions hit the obliques harder.

Are mountain climbers cardio or ab work?

Both. The plank position makes them a core-endurance exercise, while the fast leg drive raises your heart rate, so they double as low-impact cardio.

Why do my shoulders tire during mountain climbers?

You're holding a plank the whole time, so the front delts and triceps support your upper body isometrically. Keeping your hands under your shoulders and core braced spreads the load.

Related exercises

This guide is general fitness information, not medical advice. Muscle involvement varies with form, grip and individual anatomy. Consult a professional before starting a new program.