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  3. Exercises
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  5. Back
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  7. Lying Back Extension

Exercise guide

Lying Back Extension

  • Beginner
  • Compound
  • Rep-based
  • Back
  • Upper legs

This exercise targets the posterior chain, specifically the glutes and hamstrings, through a controlled hip hinge movement that builds lower back stability and functional strength.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Lying Back Extension demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Glutes
  • Hamstrings

Secondary

  • Erector spinae
  • Obliques

Equipment

  • Body weight

Setup

  1. Adjust the thigh pads so the top edge sits just below your hip bones to allow for full hip flexion without restriction.
  2. Place your feet firmly against the footplates with your ankles secured under the rollers and toes pointed slightly outward.
  3. Cross your arms over your chest or place your hands lightly behind your ears, keeping your spine in a neutral line.

How to do it

  1. Inhale and slowly hinge at the hips to lower your torso toward the floor until you feel a deep stretch in your hamstrings, maintaining a flat back.
  2. Exhale and drive your hips into the pad, using your glutes and hamstrings to lift your torso back to the starting position.
  3. Maintain a controlled 2-second descent and a 1-second ascent, stopping when your body forms a straight line from head to heels.

Form checklist

  • Keep your chin tucked toward your chest to maintain a neutral cervical spine.
  • Avoid overextending or arching your lower back past the neutral 'straight line' position at the top.
  • Ensure the movement occurs entirely at the hip joint rather than rounding or arching the lumbar spine.
  • Keep your core braced throughout the entire range of motion to protect your spine.

Pro tips

  • To maximize glute engagement, focus on 'pushing' the pad away with your hips rather than pulling your torso up with your back muscles.
  • Squeeze your glutes as hard as possible at the top of the movement to ensure they are the primary movers.

Make it harder

  • Hold a weight plate or dumbbell against your chest to increase resistance.
  • Perform the movement with a 3-second isometric hold at the top of each repetition to increase time under tension.

Frequently asked

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

Related exercises

  • 45 Degree One Leg Hyperextension Arms in Front of BodyIntermediate · erector spinae, glutes, and hamstrings
  • Around The World Superman HoldIntermediate · erector spinae, glutes, hamstrings, lats, and trapezius
  • Axle DeadliftIntermediate · calves, glutes, hamstrings, quadriceps, and trapezius
  • Band Single Stiff Leg Deadlift With Single Arm RowAdvanced · glutes, hamstrings, and trapezius

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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