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Exercise guide

Jack Jump

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

The Jack Jump is a high-intensity plyometric exercise that combines a squat with an explosive jumping jack to build lower-body power and cardiovascular endurance. It effectively targets the quadriceps and glutes while engaging the deltoids and core for stabilization and explosive movement.

Reviewed by the Crucible team · Updated June 2026

Watch the Jack Jump demonstrationGuided video and your full workout live in the Crucible app.

Muscles worked

Primary

  • Calves
  • Glutes
  • Quadriceps

Secondary

  • Hamstrings
  • Hip flexors

Equipment

  • Body weight

Setup

  1. Stand with your feet hip-width apart and your arms relaxed at your sides.
  2. Engage your core and maintain a neutral spine with your chest lifted.
  3. Lower your hips into a quarter-squat position to load your glutes and hamstrings.

How to do it

  1. Drive through the mid-foot to explode vertically, jumping as high as possible.
  2. While in mid-air, simultaneously extend your arms and legs outward to form an 'X' shape.
  3. Quickly pull your limbs back toward your midline before making contact with the ground.
  4. Land softly on the balls of your feet, immediately absorbing the impact by sinking back into the starting squat position.
  5. Exhale forcefully during the jump and inhale as you land and reset.

Form checklist

  • Land with soft knees to protect your joints from impact.
  • Keep your chest up and avoid rounding your lower back during the squat phase.
  • Ensure your knees track over your toes and do not collapse inward upon landing.
  • Maintain full core tension throughout the flight phase to stay balanced.

Pro tips

  • Focus on 'snapping' your limbs back to center as quickly as possible to increase the eccentric demand on your adductors and lats.
  • Minimize ground contact time to improve reactive power and maximize cardiovascular intensity.

Make it harder

  • Perform 'Tuck-to-Jack' jumps by pulling your knees toward your chest before extending into the star shape.
  • Wear a weighted vest to increase the load on the lower body and increase the metabolic demand.

Frequently asked

What muscles does the jack jump work?
The jack jump primarily targets the calves, glutes, and quadriceps, and also works the hamstrings and hip flexors as secondary muscles.
What equipment do you need for the jack jump?
The jack jump requires no equipment — just your body weight.
Is the jack jump good for beginners?
The jack jump is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.

Related exercises

  • 3 Point Standing HopsIntermediate · calves, glutes, hamstrings, and quadriceps
  • 4 Cone Single Foot Lateral HopsIntermediate · calves, glutes, hamstrings, and quadriceps
  • 4 Way Single Leg HopAdvanced · calves, glutes, hamstrings, and quadriceps
  • Alternate Foot HopscotchIntermediate · calves, glutes, and quadriceps

Train this with a plan, not guesswork

Crucible builds the jack jump into a precise program around your body, equipment, location, and time.

Download on the App Store