Starting with the very first yoga class I recall taking, I've heard teachers wax poetic about seated forward-bending poses, like Paschimottanasana. How helpful they are for calming the nervous system, quieting the mind, for turning inward, and so on. Meanwhile, my hamstrings would be screaming, my lower back starting to ache, and my mind racing, asking “When will this pose end, and what the heck is this teacher talking about?!” And even though my experience with seated forward bends has changed some over the years, they are still a very mixed bag for me and for many of my students.
The poses in and of themselves are not inherently good or bad, but I've observed that only about 10 percent of students find them physically easy and accessible as they are typically presented, and the other 90 percent need some serious guidance to do them safely.
Even a recent Yoga Journal Daily Insight newsletter that arrived in my inbox referred to the paradox of the forward fold, and although useful, it only told part of the story. So I thought I’d try to set the record straight (as I understand it) and also give a few helpful hints on how to do these poses so you receive these benefits with a modicum of composure without hurting yourself.
See also Achieve Uttanasana the Safe Way
Let’s start with the spine, as a bit more detail here can be helpful. First off, I like to establish the Prime Directive (huh?) without sounding too Star Trek geeky: Always begin by creating even upward lift through your entire spine. At least then you will be creating as much potential space between the individual vertebrae as much as possible, especially in the lower back where we are most concerned.
A bit about what happens with back-bending forward-bending of the spine: When you back bend, the front edges of the vertebrae move away from each other and the back edges move toward one another, wedging the spongy intervertebral discs toward the front of the spine. This turns out to be not such a big deal, because there is only a strong ligament there and no nerves for the disc to push into. However, the reverse effect is true with forward bends: When you round your spine forward, the back edges of the vertebrae move apart, the front edges toward one another, and the disc gets wedged in the posterior direction. This can be a potential problem if the discs begin to bulge into this space, because right behind the back of the vertebrae runs a very important and sensitive structure: your spinal cord. That’s right, all the bundled nerves that pass between your brain and the rest of your body, in this case your lower body, pass down just behind the discs.
If your spinal structures, ligaments, and muscles are in good health, then forward bending may not be a problem for you. But for the average person with some hip and hamstring tightness, the situation is a bit different. As you start to go into the forward bend, you are encouraged to tip the pelvis forward (good idea!), but before you have tipped very far the hamstrings act like a brake and stop any more forward movement of the pelvis. This is even more pronounced when you are sitting on your mat than when standing. In a standing forward bend, at least gravity gives the hips a little help in allowing the pelvis to rotate a bit more. But if your pelvis stops tipping, how do you fold more deeply? You do it by forward folding your vertebrae. The mildest negative consequence of this can be strain of the muscles in the lower back. But repeated effort to go deeper in a seated forward fold could potentially cause the discs to bulge backwards in the bad direction, possibly bulging into the nerves in the spinal canal, resulting in one-sided pain with symptoms even traveling down the leg. If the situation were to worsen, a ruptured disc could result. These last two situations are often related to chronic back pain and sciatica and are an unwanted side effect of poorly executed poses.
Fortunately, this does not have to be the case. One day, just a few years back, my teacher suggested we try all the seated forward bends with a bolster under the knees. A bolster! Can you believe it? At first I thought this would be a bit too much, but to my surprise and delight, I did Janu Sirsasana (Head-to-Knee Pose), Triang Mukha Eka Pada Paschimottanasana (Three-Limbed Forward Bend), Ardha Baddha Padma Paschimottanasana (Half-Bound Lotus Seated Forward Bend) and Paschimottanasana (Seated Forward Bend), and I enjoyed them all in a way I never had before. My body was at ease, my breath was relaxed, and my mind was finally quiet.
You may not need such a large prop, or any prop at all, but I do strongly suggest that you bend your knees in small increments until you find the magic moment when your pelvis can take on most of the forward-bending action, allowing for the lumbar spine to maintain a bit more neutrality (versus having to go into extension as is sometimes recommended). And even if you are in good spinal health, and can withstand a certain amount of forward rounding of the spine, if you're trying to go further into the fold by pulling strongly with the hands on the feet, a strap, or whatever you can reach, you only increase the pressure on the low back and discs in the dangerous direction.
With these modifications, it may finally be the day for you, as you fold over the thighs, that you can collect all those accolades that forward folds are said to hold.