Dangers of Lumbar Flexion in Yoga

article migration image 197 dangers of lumbar flexion in yoga jpg

Consider the number of times you flex forward at the waist or hips in a yoga class. Lower back flexion in yoga presents a number of risks when done improperly. We often hear our yoga teacher telling us to hinge at the hips instead of the lower back. Let’s consider what these cues really mean and offer in creating a safe forward bending yoga posture. First of all we have to go through a bit of yoga anatomy and biomechanics to understand the issues involved in this common movement.

Our spine is composed of twenty-four mobile vertebrae. The cervical spine includes the top seven vertebrae, while the thoracic spine is made up of the middle twelve, and the lumbar spine completes the count with the bottom five. Below the last lumbar vertebrae are the sacrum and coccyx. The sacrum is a triangular shaped bone that is actually the fused remnant of five sacral segments. The coccyx, also known as our “tailbone,” is an even smaller triangular bone that sits below the sacrum.

Both our cervical and lumbar spines take on a curve that is known as a lordosis. This lordosis essentially means that the cervical and lumbar curves’ concave sides face the front of the body; while our thoracic curve’s concave side faces the back of our body.

In-between each vertebra is an intervertebral disc. The basic functions of the discs are to act as vertebral shock absorbers and as spacers for the spinal nerves to exit the bony vertebral column. Our spinal cord runs down the inside of our vertebrae; each spinal nerve that divides from the spinal cord supplies a particular part of the body with neurological function. This explains many of the symptoms people get when they herniate or bulge a disc (burning, aching, pins and needles, tingling, pain, and weakness through particular parts of the limbs).

Intervertebral discs are round in shape with thick outer borders and jelly-like contents within the border. Each time we bend forward at the low back, the back side (posterior side) of the disc weakens. Over time, with excessive lumbar spinal loading or flexion, the disc develops microtears. Sometimes, these microtears can produce symptoms that are relatively mild; however, when the tears become more significant, symptoms become quite severe. If the thick border has enough microtears or one large tear, the inner jelly-like substance can squish out of the tear to either chemically irritate or physically compress the spinal nerves that exit the spine off of the spinal cord.

How is this complicated anatomy relevant to yoga, picking up a piece of paper off the ground, or even bending over to brush your teeth? Lumbar flexion is the movement of bending forward at the low back while rounding the spine. Due to the lordosis (lumbar curve), this position of flexion increases the likelihood of intervertebral disc microtears which then increases the chances of disc irritation, bulging, and most severely, herniation. A disc injury is one you most definitely want to avoid as they are hard to recover from and they increase your chances of low back injury recurrence; never mind the fact that they cause a lot of pain and can cause symptoms severe enough to require surgery due to neurological complications.

You must now be wondering how to keep your back safe while bending forward either on your mat or in your activities of daily living. When you bend forward, think about keeping your buttocks out and maintaining the natural curve in your lumbar spine. When you are standing straight up and when you bend forward, your lumbar curve should not change shape (much). Hinge forward at your hip joints instead of at your lumbar spine. People always say, “I bend my knees when I flex forward so I am ok!” My answer to that is that you can flex your knees all you want, but if you flex your lumbar spine as well, your back is at risk of injury. If you have to pick something up off the ground, the best way to do it is to both flex your knees AND keep you buttocks out to maintain your lumbar curve.

These principles apply to yoga as we bend forward quite a bit while on our mats. The repetitive action of improper forward flexion is dangerous, so be aware of your lordosis while you flex forward in poses while on your feet, on your back, or on your buttocks. This is even something you should think about while sitting at work; if you slouch through your lumbar spine, you are loading the discs which in time leads to microtears.

Understand your lumbar lordosis as it is your power position in everything you do. Take care of your back by being aware of how you flex forward and never compromise your back to reach further on your yoga mat.



Poor Posture and Pressure on your Spine

article migration image 511 under pressure poor posture puts more pressure on your spine jpg

Freddie Mercury was right: we’re under pressure. Nothing can be truer when it comes to your spine. It’s because of simple physics: the pressure or load on your back increases as you move away from a neutral posture. Here are the numbers: Standing straight puts 100mm of pressure on the intervertebral discs of your spine; add a forward bend while flexing or rounding your back and you’ve more than double the pressure, or 220mm. Can you see now why reaching your toes in Uttanasana or any standing forward bend before you’re ready isn’t worth the potential harm to your back?

What poor posture means to the ongoing health of your back?

Over time, poor posture causes the discs between the vertebrae to wear down and lose their ability to cushion and act as shock absorbers. The discs are pushed out towards the back from their normal position which causes bulging or herniated discs. These bulging and worn out discs can cause a more serious problem by increasing the pressure on the spinal nerves and the spinal cord itself. The result is pain in the legs, including sciatica, arms, shoulders, and neck, and problems with muscle innervations, movement patterns and the sensation of temperature, pressure and pain.

These same problems can be worsened when sitting, believe it or not. Sitting, in contrast to standing, actually increases the intradiscal load compared to standing; spinal pressure “sits’ around 140mm pressure. If you slouch (I’m talking to you desk slouchers!), spinal pressure increases to 190mm; add some weight and you’ve put a whopping 275 pounds of pressure on your spine. This is why in certain methods of yoga like Iyengar students learn standing poses before sitting ones as a general rule as they’re considered more advanced.

Sitting for long periods of time can definitely cause back pain or worsen an existing back problem. Sitting is a static posture that increases stress on the entire back, shoulders, arms, and legs, and especially the muscles of the spine. Slouching overstretches spinal ligaments and surrounding structures of the spine and nerves, blood supply is interrupted and the back muscles are overstretched.

The Solution

If you’re not a yogi yet but find yourself slouching or sitting for long periods of time during the day, your yoga can be as simple as doing the following:

  1. Getting up periodically to stand up and take the pressure off your spine

  2. Sit back into your chair so your back is supported. In yoga postures, ground evenly into your support and allow your spine to straighten up

  3. Use a lumbar roll between your lumbar or lower back and your chair. To judge the proper size of the roll, sit back in your chair, place your forearm behind your lower back between it and your chair and lean back. Your forearm is approximately the size of a lumbar roll. This works when driving too.

  4. Move! Joints don’t have much blood flow. Joints get nutrition in and waste out by physical movement. Move freely in your chair instead of sitting still for hours at a time.

For you yogis, body awareness is key to minimizing the pressure on your back. I’m not saying never practice a forward bend or a seated pose but rather know how to practice them safely. Even a seemingly friendly pose like Savasana can do harm. Sure, while lying down you’re at the lowest end of the spinal load spectrum at 25mm. As a teacher, I ask my students to roll to the side before sitting up not simply to avoid feeling dizzy and lightheaded but also to reduce the pressures on the spine. For the record, resting on your side applies 75mm pressure on your back, which is quite a bit less than pulling yourself straight up from lying flat on your back.

So, the take home message is: do the work in other poses which don’t load the spine first to lengthen your leg muscles and hamstrings, and strengthen your back before you throw yourself into a forward bend. Realize which types of poses are right for you. Gentle flexion of the spine isn’t for everybody and that’s ok. Once your body is ready, you’ll be reaping the benefits of practicing Uttanasana instead of causing harm to our back.

Read Article

More In Focus

Our unique blend of yoga, meditation, personal transformation, and alternative healing content is designed for those seeking to not just enhance their physical, spiritual, and intellectual capabilities, but to fuse them in the knowledge that the whole is always greater than the sum of its parts.


Use the same account and membership for TV, desktop, and all mobile devices. Plus you can download videos to your device to watch offline later.

Desktop, laptop, tablet, phone devices with Gaia content on screens

Discover what Gaia has to offer.

Testing message will be here