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  3. Exercises
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  5. Core & Abs
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  7. Mountain Climber Kickout

Exercise guide

Mountain Climber Kickout

  • Intermediate
  • Compound
  • Timed hold
  • Waist

The Mountain Climber Kickout is a dynamic rotational exercise that builds explosive core strength, hip mobility, and shoulder stability. It specifically targets the obliques and serratus anterior while challenging the entire upper body to maintain balance during the rotation.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Mountain Climber Kickout demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Abs
  • Deltoids
  • Obliques
  • Pectorals

Secondary

  • Serratus anterior

Equipment

  • Body weight

Setup

  1. Start in a high plank position with your hands directly under your shoulders and feet hip-width apart.
  2. Engage your core and glutes to create a straight line from your head to your heels.
  3. Spread your fingers wide and press firmly into the floor to stabilize your shoulder girdles.

How to do it

  1. Lift your right hand off the floor while simultaneously rotating your torso to the right.
  2. Kick your left leg through the space under your body, extending it fully to the right side while keeping it hovering just above the floor.
  3. Exhale sharply during the kickout, then inhale as you pull the leg back and return to the starting plank position.
  4. Immediately repeat the movement on the opposite side, alternating in a fluid, rhythmic motion.

Form checklist

  • Keep the supporting shoulder 'packed' and away from your ear to protect the joint.
  • Ensure the kicking leg stays straight and parallel to the floor without touching down.
  • Rotate your hips and chest as one unit rather than just moving your legs.
  • Maintain a flat back and avoid letting your hips sag during the transition.

Pro tips

  • Focus on the 'pull' back to center; use your obliques to drive the leg back into the plank position rather than relying on momentum.
  • Keep your weight centered over the palm of the grounded hand to prevent sliding or losing balance.
  • Look toward the direction of your kick to help facilitate full thoracic rotation.

Make it harder

  • Increase the tempo to a 'sprint' pace to turn the movement into a high-intensity cardio burner.
  • Add a full push-up between every alternating rep to increase the demand on the pectorals and triceps.

Frequently asked

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

Related exercises

  • 45 Degrees Arms PlankIntermediate · abs, deltoids, obliques, and pectorals
  • Alternate Leg Lift Tap Arms CircleIntermediate · abs, deltoids, obliques, and pectorals
  • Battling Ropes Half KneelingIntermediate · abs, biceps, deltoids, obliques, and pectorals
  • Bear WalkIntermediate · abs, calves, deltoids, hamstrings, obliques, and pectorals

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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