Williams Low Back Flexion Exercise

The low back flexion exercise is a simple way to improve your lumbar mobility and decrease your low back pain. It is a safe exercise to perform since it places minimal strain on your back and can be done while lying down. Lumbar flexion has been shown to be an effective exercise for spinal stenosis, spondylolisthesis, and lumbar facet joint problems. Lumbar flexion exercises are also known as Williams flexion exercises.

Woman stretching on exercise mat
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When to Perform Low Back Flexion

There are certain times when lumbar flexion can be beneficial to perform. People with specific conditions, such as lower back pain, typically benefit from the low back flexion exercise.

You can also use the low back flexion exercise when you are recovering from a lumbar herniated or bulging disc as part of a low back exercise progression for sciatica. You must use caution when performing this exercise. An acute disc bulge or herniation may be worsened by lumbar flexion. You must check with your healthcare provider or physical therapist before performing this exercise to ensure that it is the correct thing to do.

Who Should Not Perform Lumbar Flexion

There are certain instances where the low back flexion exercise should not be performed.

If you are performing the low back flexion exercise and your symptoms worsen, it is a good sign that you should stop the exercise and seek expert advice. Centralization (movement of spinal pain felt in the buttock, thigh, or leg to your back) of symptoms that occur as you exercise is an indication that the exercise is appropriate for you to perform. Conversely, if your symptoms worsen in your buttock, thigh, or leg as you perform the exercise it is considered a "red light." The exercise should be stopped immediately.

Remember, check in with your healthcare provider before starting this, or any other, exercise program.

How to Perform the Exercises

To perform the supine low back flexion exercise, you must find a place to lie down on your back. The surface you lie upon should be supportive, but it should still be padded enough to offer some comfort. Performing the lumbar flexion exercise on your bed is not recommended, but it can be done if there are no other alternatives.

  • Lie on your back.
  • Bend both knees up and put your feet flat on the ground.
  • Slowly bring both knees up towards your chest and grab your knees with your hands. If pressure on your knees causes knee pain, you can grab your thighs underneath your knees.
  • Gently pull your knees up close to your chest. Hold this position for three seconds.
  • Slowly allow your knees to lower back down to the starting position. Your feet should be flat on the floor and your knees should be bent.
  • Perform 10 repetitions.

Remember to monitor your symptoms as you perform this exercise. If your symptoms decrease or centralize, perform all 10 repetitions. If your symptoms worsen, you must stop and seek advice from a healthcare professional. Continuing stretching through lumbar flexion if your pain is worsening is not a good idea.

The low back flexion exercise can be performed several times per day. When your pain has subsided, this exercise can be performed once daily as part of a low back maintenance routine.

Progression of Low Back Flexion Exercises

Once the supine low back flexion exercise is easy, it may be time to progress with more advanced exercises. The progression of exercises includes:

  • Lumbar flexion in a sitting position; Sit in a chair with your knees open and your feet on the floor. Lean forward, bending at your low back. Reach your hands down towards the floor between your knees, and hold this position for two to three seconds. Return to the starting position.
  • Standing lumbar flexion: Stand with your feet about shoulder-width apart, and bend forward at the waist slowly. Reach your hands down towards your feet as far as possible, and hold this position for two to three seconds. Then, return to the starting position.

Keep in mind that Williams flexion exercises should not cause pain. If progression of the exercises causes pain, you must stop the exercise. Returning to the previous flexion exercise that does not cause pain is recommended. Checking in with your PT is also a good idea.

Many physical therapists recommend bending backward a couple of times after performing flexion exercises. This helps to offset the flexion load you placed on your spine during the exercise. Easy exercises to do are the prone press up or the standing lumbar extension. One or two repetitions are usually enough after the Williams flexion exercises. Your PT can instruct you on these extension exercises for your spine.

A Word From Verywell

If you have back pain, exercise and postural correction are your main tools in returning to normal activity and function. The low back flexion exercise may be one part of your exercise regimen to help you return to normal activity and function quickly and safely. Check in with your PT to see if lumbar flexion is the right exercise for your condition.

1 Source
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Dydyk AM. Williams Back Exercises. StatPearls [Internet]. December 2019.

By Brett Sears, PT
Brett Sears, PT, MDT, is a physical therapist with over 20 years of experience in orthopedic and hospital-based therapy.