Knees to Chest Stretch for Low Back Muscles

Develop joint range of motion and spinal flexibility

If you ever feel like you somehow miss the mark when you attempt a low back stretch—even though you know those muscles are very tight and you make every effort to release them—you are not alone. For many of us, stretching hip, neck, calf, and other muscles is a pretty straightforward deal.

But the back muscles? Not so much. These can get so tight that they become hard to reach. Finding the sweet spot for stretchiness in low back muscles can be difficult if you don't choose the right exercise for the job. 

Woman knees to chest on mat

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You may do a sustained toe touch in hopes of improving back flexibility. And yes, you're rounding your back, which technically speaking puts those muscles on a stretch, but the movement of toe touching primarily happens at the hip joints. The back rounding tends to be an offshoot of that, and it is not particularly safe, either.

That's where the knees-to-chest stretch comes in. Not only does it feel great in most instances, but it's a wonderful way to restore flexibility in your low back muscles following an afternoon of gardening or housework or after a day at the computer.

But the knees-to-chest stretch is good for more than low-back muscle release. As a range of motion exercise, in other words, a movement that increases your joint flexibility, the knees-to-chest stretch may help reduce stiffness associated with spinal arthritis and/or spinal stenosis.

For people who have osteoarthritis, range of motion exercises can help lubricate the joints, increase blood flow and deliver nutrients to the problem area.

How to Do the Knees-to-Chest Exercise

For your safety, start doing the knees-to-chest stretch with one leg only. If, after a few days, you're performing it without pain, it’s likely time to advance to lifting both legs, according to Rajter.

If you are unsure whether a double- or single-legged knees-to-chest stretch is safe given your particular back condition, speak with your healthcare provider,


  1. Lie on your back with your knees bent and your feet flat on the floor. This is called the supine position.
  2. Gently raise one bent knee up enough so you can grasp your lower leg with both hands. Interlace your fingers just under the knee.
  3. If you’re doing the two-legged version, bring one leg up and then the other. Because taking both up at the same time takes a lot of abdominal strength, starting with one and then quickly following with the other is likely safer, especially for vulnerable backs.
  4. As with the single-legged version, if you are taking both up at the same time, interlace your fingers or clasp your wrists between the lower legs, just below the knees.
  5. Gently pull your bent knee or knees toward your trunk, using your hands.
  6. While you're pulling, try to relax your legs, pelvis, and low back as much as you can. The knees-to-chest better reaches low back muscles when used passively.
  7. Hold for a few seconds.
  8. Return your leg to the floor.
  9. Repeat on the other side.

Do the stretch about 10 to 15 times, one or two times per day or as needed.

A Chain Reaction Stretch

As mentioned above, knees-to-chest works best as a passive stretch, which means keeping the legs and hips as relaxed as possible. Doing so may help you get good spinal flexion because it allows the natural chain reaction from thigh to hip to low back to occur.

In other words, when you pull your thigh to your chest, it should pull the bottom of your pelvis up just a little. This pulling will likely translate higher up until it reaches your lumbar spine area.

If you have trouble getting that lift in the lower pelvis, you might consider placing a small towel or folded blanket under your sacrum to get you started in the right direction.

According to a 2017 study published in Spine journal, science has yet to correlate tight or otherwise changed lumbar muscles with low back pain. Just the same, many people find that a good release is the best medicine when trouble sets in.

Frequently Asked Questions

  • What is the best lower back stretch?

    The knees-to-chest stretch is the best stretch for your lower back. This gentle move stretches several muscles across the lower back and buttocks.

  • What muscles are stretched when you pull your knees to your chest?

    The knees-to-chest stretch helps to loosen up the erector spinae, latissimus dorsi, gluteus medius, gluteus minimus, and gluteus maximus muscles, as well as the thoracolumbar fascia.

  • Is the knees-to-chest stretch safe for people with back pain?

    Yes, for the most part, the knees-to-chest stretch is a gentle stretch that is safe for people who have back pain from arthritis or disc problems.

    However, if you experience any pain while doing this stretch, talk to your doctor or physical therapist. They may recommend stretching just one knee to the chest at a time.

4 Sources
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. AFPA Health, Nutrition, and Fitness. Bad discs and sciatica: how to fix them yourself.

  2. Arthritis Foundation. Exercising with osteoarthritis.

  3. Arthritis Foundation. How exercise helps your joints.

  4. Ranger TA, Cicuttini FM, Jensen TS, et al. Are the size and composition of the paraspinal muscles associated with low back pain? A systematic review. Spine J. 2017;17(11):1729-1748. doi:10.1016/j.spinee.2017.07.002

By Anne Asher, CPT
Anne Asher, ACE-certified personal trainer, health coach, and orthopedic exercise specialist, is a back and neck pain expert.