[i] researchers looked at the water content of the intervertebral discs after a period of exercise that involved 15 repetitions of flexion, extension and left and right rotation. They used MRI as the technique of choice and measured the water content of the intervertebral discs before and after exercise. They also measured what happened after 30 minutes of just pure lying down.
They recruited 40 medical students for the study (twenty-six males and fourteen females, average age 25.6 years old) without a recent history of back pain or sciatica nor did they have any previous spinal surgeries.
These researchers imaged the subjects using a standard 1.5 Tesla [which is the magnet power]. It was important to image at the same time of the day because the discs lose height and water slowly over the course of the day. And in imaging at the same time of day, it ensured to minimize the diurnal effects (the natural changes).
Interestingly, after they carefully mapped out the water with a technique called ‘T2 mapping’, they found that the discs lost water with the exercise. However, when they imaged the subjects immediately after the exercise, they instructed them to lie down on the MRI table for thirty minutes before a third scan was done.
What they found was the spine recovered all the water loss when the subjects laid down for 30 minutes.
Take home message: after exercise, it is always a good idea to lie down, even if it is for 5 minutes, to allow your spine to rehydrate.
In 2000, I began to string the research together and developed an exercise to rehydrate the spine. It is called chair-care and is recommended to those that have back pain while sitting. Or it is also prescribed to those that want to prevent back pain from sitting.
Having only a theory, I put the offloading exercise to the test with my patients when I practiced in the little coastal towns of Ucleulet and Tofino between 2000 and 2007. Of course, I tried the exercise on myself first to see if it was safe. And after continuing to receive positive outcomes from those select patients I thought it could benefit, I decided that it was necessary to try and get it published.
This exercise I believed could rehydrate the discs of the spine after a period of sitting. And to test to see if I was correct, I too used MRI like the researchers above used. But instead, I measured the distance between the vertebra and low and behold, there was a height change. I know there was a very small sample size, but since the 2010 publication in The Spine Journal [ii] others have reproduced the work.[iii]
It is exciting to see other researchers looking to find effective ways to recuperate the water content from either exercise, or prolonged sitting.
Water is the source of our structure, and watching where and why it moves will provide large rewards in the scientific investigation of back pain.
[i] Kou Chokan, MD, Hideki Murakami, MD, Hirooki Endo, MD, Yoshikuni Mimata, MD, Daisuke Yamabe, MD, Itsuko Tsukimura, MD, Ryosuke Oikawa, MD, and Minoru Doita, MD : Evaluation of Water Retention in Lumbar Intervertebral Disks Before and After Exercise Stress With T2 Mapping.; SPINE Volume 41, Number 7, pp E430–E436 2016
[ii] Jerome C.J. Fryer, DC, Jeffrey A. Quon, DC, PhD, Francis W. Smith, MD Magnetic resonance imaging and stadiometric assessment of the lumbar discs after sitting and chair-care decompression exercise: a pilot study The Spine Journal 10 (2010) 297–305
[iii] C. Phimphasak, M. Swangnetr, R. Puntumetakul, U. Chatchawan and R. Boucaut. Effects of seated lumbar extension postures on spinal height and lumbar range of motion during prolonged sitting. Ergonomics, 2015 http://dx.doi.org/10.1080/00140139.2015.1052570