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  5. Shoulders
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  7. Overhead And Under Knee Clap

Exercise guide

Overhead And Under Knee Clap

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

This dynamic exercise combines high-knee coordination with rhythmic arm movements to engage the core, hip flexors, and shoulders while improving cardiovascular endurance. It effectively targets the lower abdominals and quadriceps through active hip flexion and trunk stabilization.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Overhead And Under Knee Clap demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Abs
  • Calves
  • Deltoids

Secondary

  • Obliques
  • Serratus anterior

Equipment

  • Body weight

Setup

  1. Stand upright with your feet hip-width apart and your core engaged.
  2. Position your arms at your sides with your shoulders relaxed and chest open.
  3. Distribute your weight evenly across both feet, maintaining a slight bend in the knees.

How to do it

  1. Inhale and reach both arms directly overhead, clapping your hands together at the peak of the movement.
  2. Exhale as you lift your right knee toward your chest while simultaneously swinging both arms down to clap your hands underneath your right thigh.
  3. Return your right foot to the floor and immediately reach back overhead for another clap.
  4. Repeat the movement by lifting the left knee and clapping underneath it, alternating sides in a rhythmic tempo.

Form checklist

  • Maintain an upright torso; avoid rounding your lower back excessively when clapping under the knee.
  • Drive your knee up to at least hip height to maximize lower abdominal engagement.
  • Keep your core braced throughout the entire movement to maintain balance.
  • Land softly on the balls of your feet to protect your joints and engage the calves.

Pro tips

  • Focus on a forceful exhale as you clap under the knee to deepen the contraction of the transverse abdominis.
  • Keep your arms fully extended during the overhead clap to maximize the range of motion for the deltoids and pectorals.

Make it harder

  • Increase the speed of the movement to turn it into a high-intensity cardio interval.
  • Add a small hop as you switch legs to incorporate plyometric power and increase calf activation.

Frequently asked

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

Related exercises

  • Alternate Front Kick In Place With Arm CirclesBeginner · abs, calves, deltoids, and pectorals
  • Boxing Cross Hook CrossIntermediate · abs, calves, deltoids, obliques, pectorals, and quadriceps
  • Double Punch Front Leg LiftBeginner · abs, calves, deltoids, and pectorals
  • Jumping Air Bike Arm SwingIntermediate · abs, calves, deltoids, and obliques

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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