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  7. Back Leg Lift Jack

Exercise guide

Back Leg Lift Jack

  • Beginner
  • Compound
  • Rep-based
  • Lower legs
  • Upper legs
  • Waist

A dynamic standing cardio and core exercise that combines a traditional jumping jack with a rear leg extension to target the glutes and improve balance. This compound movement builds coordination while engaging the chest and shoulders through active arm swings.

Reviewed by the Crucible team · Updated June 2026

Watch the Back Leg Lift Jack demonstrationGuided video and your full workout live in the Crucible app.

Muscles worked

Primary

  • Abs
  • Glutes
  • Hamstrings
  • Obliques

Secondary

  • Erector spinae
  • Quadriceps

Equipment

  • Body weight

Setup

  1. Stand upright with your feet together and arms resting at your sides.
  2. Engage your core and keep your chest lifted with shoulders pulled back and down.
  3. Maintain a slight bend in your knees to absorb impact.

How to do it

  1. Jump both feet out wide while swinging your arms overhead in a standard jumping jack motion.
  2. Jump your feet back together while bringing your arms down to chest height in a controlled 'fly' motion to engage the pectorals.
  3. Immediately lift one leg straight back behind you, squeezing the glute, while keeping your hips square to the front.
  4. Exhale as you jump out and as you lift the leg; inhale as you return to the neutral standing position.

Form checklist

  • Keep your torso upright and avoid leaning forward excessively during the leg lift.
  • Land softly on the balls of your feet to minimize impact on your knees and ankles.
  • Squeeze your glutes at the top of the leg lift rather than arching your lower back.
  • Maintain a rhythmic tempo, ensuring the transition between the jack and the lift is fluid.

Pro tips

  • Focus on a strong 'mind-muscle connection' by squeezing your shoulder blades and chest during the arm movements.
  • Keep your standing leg slightly bent during the leg lift to increase quadriceps and calf stability.

Make it harder

  • Add a resistance band just above your knees to increase the challenge for the glutes and abductors.
  • Hold light dumbbells (1-3 lbs) to increase the demand on the deltoids and pectorals.

Frequently asked

What muscles does the back leg lift jack work?
The back leg lift jack primarily targets the abs, glutes, hamstrings, and obliques, and also works the erector spinae and quadriceps as secondary muscles.
What equipment do you need for the back leg lift jack?
The back leg lift jack requires no equipment — just your body weight.
Is the back leg lift jack good for beginners?
Yes. The back leg lift jack is a beginner-friendly movement and a strong foundation to build on.

Related exercises

  • Barbell Lunge TwistIntermediate · abs, glutes, hamstrings, obliques, and quadriceps
  • Bosu Ball Step-Up High Knee Air TwistIntermediate · abs, calves, glutes, hamstrings, obliques, and quadriceps
  • Elevated Lunge T Spine RotationIntermediate · abs, glutes, hamstrings, obliques, and quadriceps
  • Fixed Feet Sit-Up StandIntermediate · abs, glutes, hamstrings, obliques, and quadriceps

Train this with a plan, not guesswork

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

Download on the App Store