Forward bends can be quite problematic for the lower back. When we bend forward, we tend to do too much of the movement in the lower back. The lumbar spine is quite mobile in this direction, but excessive movement here is a frequent cause of back pain. Lower back pain in turn is the most common health complaint in the US. Last week we focused on alignment in the upper back and neck in forward bends. This week we will focus on lower back and hip alignment.

Understanding herniated discs

We often don’t know what actually gets injured when we hurt our lower backs. However, one common injury from excessive forward bending is a herniated intervertebral disc. Why are herniated discs an issue? When a disc bulges or ruptures, it can compress a nerve root exiting the spinal cord, triggering significant and sometimes even debilitating pain.

Unlike the nerve roots, the spinal cord itself is relatively well protected from disc herniation. While the spinal cord lies directly behind the discs, a long tough ligament called the posterior longitudinal ligament protects it from bulging discs. Because this ligament lies within the spinal canal, it is by necessity narrow, which means that it cannot protect the nerves exiting sideways from the spinal cord. A herniated disc typically bulges to the rear and to one side because the longitudinal ligament generally prevents it from bulging straight back. So while the spinal cord is protected, the nerve roots are not, and their compression can trigger severe pain. 

The majority of disc herniations occurs between the two lowest lumbar vertebrae (L4-L5) or between the lowest lumbar vertebra and the sacrum (L5-S1).  A herniated disc is also commonly referred to as a slipped disc, but this is a misnomer as the discs cannot slip. Each disc is fused to the vertebral bodies above and below.

A ruptured or herniated disc is a more severe injury than a bulging disc. In a bulging disc the tough outer layer of the disc (the annulus fibrosus) remains partially intact. But even the majority of disc herniations heals within weeks or months, and very few require surgery. Nonetheless we are better off not injuring them in the first place. In addition, sometimes the pain can become chronic because we keep re-injuring a disc through continued poor biomechanics.

A healthy and a herniated disc, showing the normal pattern of damage.

A healthy and a herniated disc, showing a typical pattern of damage.

Keeping your back safe

So what can you do to keep your lower back safe in forward bends?

1. Stop following the path of least resistance

When we move unconsciously, we use strong muscles to move flexible joints, and we avoid using weak muscles to move tight joints. Repeating the same movement patterns rather than creating new ones requires less mental effort. Using strong muscles to move flexible joints also requires less physical energy than using weak muscles to move stiff joints. Both reasons relate to the fact that evolutionarily speaking, we are built for efficiency. But efficiency, while it helps prevent starvation, does not increase well-being and does not prevent injuries. 

Forward bends intend to flex your hips and your entire spine. But because of tight hips, most of us do too much of the forward bending in the lower back, and not enough in the hip joints. The longer we favor flexing the spine instead of the hips, the tighter our hip joints get. And the tighter the hips, the more common and severe lower back pain becomes.

Don’t believe me that you underuse your hip joints? Try this simple exercise: Lie on the floor and notice that your lower back is off the floor. Inhale one knee towards your chest and hold your shin with your hands. Notice that your lower back is now in contact with the floor. This movement is a very gentle hip flexion that doesn’t even stretch the hamstrings because of the bent knee. Yet even here we do as much of the work as we can in the lumbar spine instead of the hip joints.

To stop following the path of least resistance in forward bends means learning how to do an anterior hip tilt. Anterior hip tilt means moving the tops of the hips forward towards the knees. This movement increases flexion in the hips, while decreasing it in the lower back.

2. Avoid bending forward and twisting your spine simultaneously

In a simple forward bend, the discs bulge straight back into the posterior longitudinal ligament of the spine. This usually prevents disc damage in this direction. If you combine a forward bend with a spinal twist, the direction of the force is to the back and one side, where there is no ligament to protect the disc. Thus bending forward while twisting with too much force is particularly likely to injure a disc.

The solution, part 1: Avoid poses that are designed to bend and twist your spine at the same time, or modify them to reduce the twisting motion. For example, in Janu Sirsasana, don’t bend forward directly over the straight leg because that requires a twist to that side. Instead, bend forward inside the straight let, keeping your breast bone pointing in the same direction as your pubic bone, centered between your hip crests.

The solution, part 2: Avoid bending forward in spinal twists, which is unfortunately often the path of least resistance. In poses such as Marichyasana III, notice the tendency to collapse the front of your chest as you twist in order to get your arm more fully around your bent leg. When your chest collapses, your back is bending forward. To reduce the forward bend which makes the spinal twist more dangerous, inhale your breastbone away from your bellybutton and send energy down into your sit bones and up and out through the crown of your head. When you do this, notice the increased feeling of space along the spine and the reduction of pressure in your lumbar discs. Also note that you can actually twist a little farther when you don’t forward bend at the same time, though that is not the main point! The health of your spine is.

3. Work on lengthening your hamstrings in poses that make it impossible to cheat

If your hamstrings are particularly tight, just building awareness may not be enough. Neutral hip alignment in many poses is simply impossible if your hamstrings are tight. If you use standing or seated forward bends to try to lengthen your hamstrings in order to reduce the workload on your lower back, you may actually injure your lower back instead! Not so useful.

The solution is to lengthen your hamstrings in poses that don’t allow you to stretch the lower back instead. Simply put, this means reclining hip stretches, because when you lie on your back and flex your hips, you can’t really cheat by rounding your lower back. Lying on the floor, you can flex your lower back only a few degrees before it flattens against the floor and can go no farther. Resting against the floor also means that your lower back is perfectly safe here. In seated or standing forward bends, by comparison, it tends to receive most of the strain.

Do your hips flex less than 90 degrees in Supta Padangusthasana (reclining straight-legged hamstring stretch)? Then I would suggest avoiding standing and seated forward bends entirely for the time being. Instead, when your teacher instructs any seated forward bend, lie down on your back facing a wall. Then bring your legs up a wall in the same shape as what your teacher is instructing for the seated variation. Dial in the stretch intensity by how close you place your sit bones to the wall. 

Most of us do suffer from tight hamstrings, but fortunately lengthening muscles is relatively straightforward. Noticeable changes happen within a matter of weeks if you are consistent in your exercises, emphasize surrender in your stretches, and practice with reasonable intensity. 

4. Strengthen postural muscles that protect your spine

Recent research points to a correlation between persistent back pain and poorly functioning multifidus muscles. Never heard of them? Don’t worry, most people haven’t. Each multifidus muscle connects the transverse process of one vertebra to the spinous process of the next higher vertebra, or the one above that. These muscles, when they function well, can keep the vertebrae in more neutral alignment, and in particular, can prevent excessive spinal flexion and thus can reduce the internal disc pressure that can lead to herniations.

So, how can you learn to strengthen your multifidi if they aren’t already doing their job? One way is to keep your hips level in poses in which you are tempted to lift one up behind you. These poses are 3-legged Table, 3-legged Down Dog, and Warrior 3.

5. Tune up your multifidi

Come into table, and inhale one leg up. Notice whether you lifted your hip when you lifted the leg. Most of us do, because it allows us to lift the leg higher with objectively less effort. It also creates a subjective reduction in effort. It allows us to use strong muscles we are good at engaging, while avoiding engaging muscles we are not good at engaging. In other words, moving this way makes us feel efficient and accomplished, as it feels like we are going farther with less effort. But guess what: Those muscles you are avoiding engaging by lifting your hip when lifting your leg? Those are your multifidi.

Observe what happens when you slowly lower the hip of the lifted leg towards neutral. To make this happen, you can focus on lifting more through the inner thigh while letting the outer hip descend. As the hip lowers, can you feel a “cinching down” sensation ripple along your spine? It’s quite a deep sensation, below the big superficial spinal muscles. If so, those are your multifidi engaging. Simply add these 3 poses to your practice and focus on keeping your hips more neutral in them. If you do, you can have a significant impact on your spinal health and your overall wellbeing. I always inhale one leg up behind me before stepping forward from Down Dog, and I always emphasize relatively neutral hips in this movement. This way I build multifidi exercises into each yoga practice.

6. Lengthen your spine when you bend forward

Keeping your spine long helps protect your spine in forward bends as well as in backbends. The more the front edge of the disc compresses, the greater the internal disc pressure, which is the direct cause of herniated discs. (The pressure can rise from 17psi in a lumbar disc in a reclining person to over 300psi when lifting a heavy object with a rounded lumbar spine.) Keeping your spine long maintains more space between the vertebrae, thus reducing pressure inside the discs. How do you keep the spine long in forward bends? Engage your multifidi.

However, just telling people to engage their multifidi doesn’t work, because these deep postural muscles are challenging to engage consciously, even for people who actually know that they exist. Instead I use a more experiential instruction to create the necessary contraction.

One instruction for seated forward bends I give is to think of the movement as a lifting up and over, rather than a bending down. To make this concept more intuitive I use the image of a cresting and crashing wave. Have you have ever watched a crashing wave closely? Have you noticed how the water actually runs back and UP the front surface of the wave before moving forward and finally crashing down? Turning a forward bend into an act of “lifting up, over, and forward”, instead of collapsing down, quite naturally lengthens the spine and helps protect it. If you feel energy moving up along the spine, if you feel a “cinching down” rippling up the spine, you have figured out how to use your multifidi. 

7. Practice with appropriate intensity to keep your back safe

The final point I want to emphasize for safe forward bends here is that forward bends have a cooling, down-regulating effect. They increase your capacity to relax and surrender. While seated forward bends appear in most beginner’s syllabi, they have great potential for causing injury when done with poor alignment and with too much effort.

Straight legged seated forward bends are particularly problematic. The extended knees tighten the hamstrings, causing the hips to rotate back even more than bent-knee seated poses. The other reason why straight-legged seated forward bends are particularly dangerous is that many people get preoccupied with wanting to touch their toes. This ego-gratifying but essentially meaningless detail tempts many people into stretching with too much force in poses like Paschimottanasana. And all that force goes into overstretching the lower and middle back, NOT into increasing hip and hamstring stretches. If you approach forward bends the way you do a Warrior I, for example, you are much more likely to injure yourself. But you completely miss the point of forward bends, to boot.