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  5. Shoulders
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  7. Kneeling Wrist Sinkers

Exercise guide

Kneeling Wrist Sinkers

  • Beginner
  • Compound
  • Rep-based
  • Shoulders
  • Upper arms
  • Waist

Kneeling Wrist Sinkers are a foundational mobility and strengthening exercise that targets the forearm flexors and improves wrist joint resilience. This movement uses controlled bodyweight to increase the range of motion and load-bearing capacity of the wrists.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Kneeling Wrist Sinkers demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Forearms

Secondary

  • Abs
  • Obliques
  • Serratus anterior

Equipment

  • Body weight

Setup

  1. Kneel on a soft surface with your hands placed flat on the floor, fingers pointing straight ahead.
  2. Position your shoulders directly over your wrists and your knees under your hips.
  3. Ensure your arms are fully extended with elbows locked.

How to do it

  1. Inhale and slowly lean your torso forward, shifting your shoulders past your fingertips while keeping your palms glued to the floor.
  2. Hold the end-range stretch for 1-2 seconds, feeling the tension in your forearms.
  3. Exhale and push through your palms to return to the starting vertical position.
  4. Perform the movement with a slow, rhythmic tempo, focusing on a deep stretch.

Form checklist

  • Keep your elbows completely straight throughout the movement.
  • Do not allow the heels of your hands to lift off the floor.
  • Maintain a neutral spine and avoid shrugging your shoulders toward your ears.
  • Only lean forward as far as your current mobility allows without sharp pain.

Pro tips

  • Actively 'claw' the floor with your fingertips to engage the deep flexors of the forearm.
  • Rotate your elbow pits forward (external rotation) to stabilize the shoulder and isolate the wrist.

Make it harder

  • Walk your knees further back to increase the percentage of bodyweight loaded onto the wrists.
  • Perform the sinkers from a full plank position to significantly increase the resistance.

Frequently asked

What muscles does the kneeling wrist sinkers work?
The kneeling wrist sinkers primarily targets the forearms, and also works the abs, obliques, and serratus anterior as secondary muscles.
What equipment do you need for the kneeling wrist sinkers?
The kneeling wrist sinkers requires no equipment — just your body weight.
Is the kneeling wrist sinkers good for beginners?
Yes. The kneeling wrist sinkers is a beginner-friendly movement and a strong foundation to build on.

Related exercises

  • Boxing HookIntermediate · biceps, deltoids, forearms, lats, obliques, pectorals, and triceps
  • Boxing Jab With Bag And GlovesIntermediate · biceps, deltoids, forearms, and serratus anterior
  • Jumping Pull-UpIntermediate · biceps, deltoids, forearms, and lats
  • Kneeling Finger PressIntermediate · forearms

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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