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  1. Home
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  3. Exercises
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  5. Core & Abs
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  7. Plank Leg Lift Mountain Climber

Exercise guide

Plank Leg Lift Mountain Climber

  • Intermediate
  • Compound
  • Timed hold
  • Waist

This compound core exercise combines a glute-focused leg lift with a dynamic mountain climber to challenge stability, hip mobility, and total-body coordination. It effectively targets the entire posterior chain while demanding high levels of core tension and shoulder stability.

Reviewed by the Crucible Fit team · Updated June 2026

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

Muscles worked

Primary

  • Abs
  • Deltoids
  • Hamstrings
  • Obliques

Secondary

  • Erector spinae
  • 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. Distribute your weight evenly across your palms and the balls of your feet.

How to do it

  1. Inhale and lift your right leg toward the ceiling, keeping it straight to engage the glutes and hamstrings.
  2. Exhale as you drive that same right knee toward your chest, pulling your navel toward your spine to maximize abdominal contraction.
  3. Inhale as you extend the leg back out and return to the starting high plank position.
  4. Repeat the sequence with the left leg, alternating sides with a controlled, steady tempo.

Form checklist

  • Keep your hips level and square to the floor; do not let them sag or pike during the leg lift.
  • Maintain a neutral neck by looking at a spot on the floor about six inches in front of your hands.
  • Push actively through the floor to keep your shoulder blades spread and stable.
  • Ensure the knee drive is a controlled crunch rather than a momentum-based swing.

Pro tips

  • At the peak of the leg lift, pause for a split second to maximize the glute contraction before driving the knee forward.
  • Focus on 'protracting' your shoulders (pushing the floor away) during the knee drive to create more space for the leg to move.

Make it harder

  • Perform the knee drive toward the opposite elbow to increase oblique activation.
  • Add a push-up between each alternating leg sequence to increase the demand on the chest and triceps.

Frequently asked

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

Related exercises

  • Alternate Single Leg Raise PlankIntermediate · abs, deltoids, hamstrings, and obliques
  • Bear Plank Floating Leg ExtensionIntermediate · abs, deltoids, hamstrings, and obliques
  • Bear Plank Floating MarchIntermediate · abs, calves, deltoids, hamstrings, and obliques
  • 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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