Each and every one of us, for the rest of our lives, will be engaged in the battle against gravity. It is a constant force applied to us every single day. Coupled with the hours we sit, the sports we play, and the unexpected trips and falls we might endure, this translates to massive compressive forces placed upon the spine.
To deal with this, the spine has ‘discs’ between each vertebra. They are fluid-filled shock absorbers and prevent bone-on-bone friction. Since they do not have a blood supply, nourishing the discs occurs via osmosis. Movement throughout the spine is thus vital to preserve and feed these structures, so that the discs can prevent excessive wear and tear to the vertebral column.
Incidental spinal movements throughout the day create a physical pumping effort which shunts nutrient-bearing fluids in, and stale fluids out. Well-hydrated discs become plump which gives better bony separation and ultimately renders the spine more able to accommodate compression, impact and jarring.
The force of gravity means the discs naturally lose fluid throughout the day – people can lose up to 2cm in height by the end of the day. Sleeping horizontal at night allows the natural fluid exchange within the discs to be carried out – fresh nutrients are drawn in, whilst stale fluid is expelled.
Prolonged sitting is a risk factor for maintain healthy discs. In the first two hours of sitting, one can lose up to 10% of intradiscal fluid. Slumped sitting is particularly bad for the discs, as is any low activity posture.
The majority of back pain that exists today, is often due to compressive forces applied to the spine. In the age of chronic sitting, performing spinal decompression exercises daily may serve the overwhelming majority of back pain sufferers.
Using a back block is an easy and effective way to perform spinal decompression. Lying backwards passively over a block exerts lumbar traction and both stretches the compressed disc wall and passively elongates tight local muscles and ligaments that have tethered and contracted the spine down. This method works by stimulating pressure changes within the intervertebral discs by alternately loading and unloading the discs within their physiological range. The physical separation of the spinal segments also counters the fluid loss and the slow deflation of the discs.
Using the back block
- Lie on the floor on your back with your knees bent so that your feet are touching the floor.
- Lift your backside off the floor and slide the block, on its flattest edge, to rest lengthways under your sacrum (the hard flat bone at the base of your spine).
- Straighten your arms above your shoulders to rest on the floor, then straighten out one leg at a time until both legs are relaxed.
- Remain in this position for 60 seconds only. Expect some initial discomfort as your body adapts to the position.
- For a greater effect, you may progress to using the block on its second highest edge on subsequent sets. Always start using the lowest edge first.
- After 60 seconds of lying over the back block, bring your arms back down to your sides. Then return your legs, one at a time, to the starting position (take care as this can be uncomfortable).
- See the following pictures to reference the correct positioning of the block.
The challenge when in the final back block position, is to let go of all muscular tension. If you are suffering back pain, your body may resist completely relaxing your back over the block. Take your time. With each exhale, attempt to let the muscles around your pelvic floor, hip flexors and lower back give way, so that you can begin to feel the traction sensation building up through your spine.
- Lie on your back with your knees bent and feet on the floor. In this position note that your lower back is somewhat raised (or arched) off the floor.
- Flatten your back against the floor (push fairly hard) and then relax. Do this fairly quickly for about 30 seconds, aim for 30 repetitions.
Having just followed the back block routine, your back may now be feeling slightly sensitive. Traction through the spine is a force we are not usually accustomed to. It can be a mildly painful experience following this decompression exercise. The pelvic rock is a gentle way of alleviating any immediate discomfort experienced through the lower back after using the back block.
- Raise your knees, one at a time, towards your chest so that your thighs are parallel to the floor. Cross both ankles and relax your knees outwards.
- Place your hands around the outside of each thigh to hold your knees so that all the weight of your lower body is held in your hands.
- Gently oscillate your knees towards your chest for 30 seconds, do this rhythmically as if rocking a baby to sleep.
The knees rocking movement is an excellent way to restore lumbar flexion range of motion. This helps to loosen the large lumbar erector spinae muscles of the lower back and facilitate further, the imbibition of fluid into the intervertebral discs.
- Start in the same position as for the knees rocking exercise but instead, interlace your fingers behind your head.
- Using your lower abdominals, bring your knees towards your chin, attempting to lift your backside off the floor.
- Try to keep your stomach pulled inwards as you lower your legs perpendicular to the floor. Ensure your thighs do not pass beyond this return point (90 degrees). This will cause your back to arch and potentially become painful.
- Do 15 repetitions.
The reverse curl exercise activates the abdominal corsetry that serves to lift your spinal segments off one another. In this way, the lower abdominals act as the body’s own spine sparing function enabling spinal decompression.
- Start on all fours, then sit your backside onto your heels.
- Keep the knees pointing outwards at roughly 45 degrees, then lower your torso forwards with the arms stretched out in front of you.
- Relax in this position for up to 30 seconds.
This yoga pose has many benefits but is used in this instance as another means for spinal decompression. If you have a history of hip, knee or ankle injuries, you may struggle to morph your body into this position. If so, some simple forward bending off the edge of a seat, or toe touches will suffice. See the below suggestions.
Forward bending (below left), Toe touches (below right)
Since compression builds up in our spines throughout the day, the best time to perform this routine is at the end of the day. You can however follow this routine as many times as you like. Remember, in the mornings after sleep, you would have already been somewhat decompressed throughout the night. It would thus be less effective doing these exercises upon waking. Ideally, you would attempt to do this routine between 12 and 3pm, and just before going to bed.
Back blocks are available for purchase at Cartwright Physcialtherapy.