Skip to content
Crucible Fit
  • The Crucible
  • The Week
  • Programs
  • Train Your Way
  • Pricing
Get Crucible
  • The Crucible
  • The Week
  • Programs
  • Train Your Way
  • Apple Watch
  • Pricing
  • FAQ
  • Training Guides
Get Crucible
Crucible Fit

A daily functional fitness test for iPhone, Apple Watch and Android. Stations, reps and the Crux, sized to your readiness and your kit.

Download on the App StoreGet it on Google Play

Crucible Fit

  • The Crucible
  • The Week
  • Programs
  • Train Your Way
  • Apple Watch
  • Pricing

Explore

  • Training Guides
  • Exercise Library
  • FAQ
  • Press
  • Support

Legal

  • Terms and Conditions
  • Privacy Policy
  • Consumer Health Data Notice

CRUCIBLE FIT™ and Crux by Crucible Fit are trademarks of Crucible Fit, LLC.

© 2026 Crucible Fit, LLC. All rights reserved. Apple, the Apple logo, iPhone and Apple Watch are trademarks of Apple Inc., registered in the U.S. and other countries. App Store is a service mark of Apple Inc. Google Play and the Google Play logo are trademarks of Google LLC.

  1. Home
  2. /
  3. Exercises
  4. /
  5. Core & Abs
  6. /
  7. Half Wipers Bent Leg

Exercise guide

Half Wipers Bent Leg

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

This beginner-friendly rotational exercise targets the obliques and deep core while improving spinal mobility. By keeping the knees bent, you reduce the lever length, allowing for better control and focus on the lateral abdominal muscles.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Half Wipers Bent Leg demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Abs
  • Obliques

Secondary

  • Erector spinae
  • Glutes
  • Quadriceps

Equipment

  • Body weight

Setup

  1. Lie flat on your back with your arms extended out to the sides in a 'T' shape, palms facing down for stability.
  2. Lift your legs and bend your knees to a 90-degree angle, creating a 'tabletop' position with your shins parallel to the floor.
  3. Press your lower back firmly into the ground to engage your transverse abdominis.

How to do it

  1. Inhale as you slowly lower your knees to one side, maintaining the 90-degree bend and keeping both shoulders glued to the floor.
  2. Stop the descent just before your knees touch the ground or when you feel your opposite shoulder starting to lift.
  3. Exhale and use your obliques to pull your legs back to the center starting position.
  4. Repeat the movement on the opposite side, alternating back and forth with a controlled 2-1-2 tempo.

Form checklist

  • Keep your shoulder blades in constant contact with the floor throughout the entire range of motion.
  • Maintain a consistent 90-degree angle at both the knees and the hips.
  • Avoid using your arms to push off the floor; ensure the movement is driven by your core.
  • Move with slow control rather than using momentum to swing your legs from side to side.

Pro tips

  • Focus on the mind-muscle connection by imagining your ribcage rotating toward the opposite hip to initiate the return to center.
  • Squeeze your knees and ankles together throughout the movement to increase lower abdominal and adductor engagement.

Make it harder

  • Increase the lever length by slightly straightening your legs while maintaining control of your lower back.
  • Add a 2-second isometric hold at the bottom of the range of motion on each side to increase time under tension.

Frequently asked

What muscles does the half wipers bent leg work?
The half wipers bent leg primarily targets the abs and obliques, and also works the erector spinae, glutes, and quadriceps as secondary muscles.
What equipment do you need for the half wipers bent leg?
The half wipers bent leg requires no equipment — just your body weight.
Is the half wipers bent leg good for beginners?
The half wipers bent leg 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
  • 90 To 90Beginner · abs, glutes, obliques, and quadriceps
  • 90 To 90 SwitchIntermediate · abs, glutes, obliques, and quadriceps
  • Air BikeIntermediate · abs 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.

Download on the App StoreGet it on Google Play

See how a Crucible works