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  3. Exercises
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  5. Core & Abs
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  7. Bridge - Mountain Climber Cross Body

Exercise guide

Bridge - Mountain Climber Cross Body

  • Intermediate
  • Compound
  • Timed hold
  • Lower legs
  • Upper legs
  • Waist

This dynamic core exercise combines a high plank with rotational knee drives to target the obliques and deep core while challenging shoulder stability. It effectively builds rotational power and improves functional stability through the entire anterior chain.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Bridge - Mountain Climber Cross Body demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Deltoids

Secondary

  • Glutes
  • Hamstrings
  • Hip flexors

Equipment

  • Body weight

Setup

  1. Start in a high plank position with your hands placed 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. Maintain a neutral neck by looking at the floor slightly ahead of your hands.

How to do it

  1. Exhale as you drive your right knee toward your left elbow, rotating your hips slightly while keeping your shoulders square to the floor.
  2. Inhale as you return your right foot to the starting position with control.
  3. Repeat the movement on the opposite side, driving your left knee toward your right elbow.
  4. Maintain a steady, controlled tempo, alternating sides for the duration of the set.

Form checklist

  • Keep your hips level with your shoulders; do not let them sag or pike upward.
  • Maintain a strong 'push' through the floor to keep your shoulder blades from winging.
  • Ensure your knee travels across the midline of your body to maximize oblique engagement.
  • Keep your core braced tightly to prevent your lower back from arching.

Pro tips

  • Focus on the 'crunch' sensation in your obliques at the peak of the movement rather than just moving your legs quickly.
  • Slow down the tempo to increase time under tension and force your stabilizers to work harder.
  • Imagine pulling your belly button toward your spine throughout the entire movement to deepen transverse abdominis engagement.

Make it harder

  • Add a two-second pause and a hard squeeze when the knee reaches the opposite elbow.
  • Perform the movement with your hands on an unstable surface, like a BOSU ball or medicine ball, to increase shoulder and core demand.

Frequently asked

What muscles does the bridge - mountain climber cross body work?
The bridge - mountain climber cross body primarily targets the deltoids, and also works the glutes, hamstrings, and hip flexors as secondary muscles.
What equipment do you need for the bridge - mountain climber cross body?
The bridge - mountain climber cross body requires no equipment — just your body weight.
Is the bridge - mountain climber cross body good for beginners?
The bridge - mountain climber cross body 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 Front Kick In Place With Arm CirclesBeginner · abs, calves, deltoids, and pectorals
  • Alternate Single Leg Raise PlankIntermediate · abs, deltoids, hamstrings, and obliques
  • Arms Circle Marching On SpotBeginner · deltoids 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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