Very useful information on Lumber Support from a Kayak's blog
Posted Mar 27 2010 6:04am
I found this article on a Kayak Fishing and Paddling blog. Although its probably something us back pain suferers could not do the interesting information in the article is worth reading.
"Kayaks, Back Problems, Lumbar Support - and the Simple Truth...
So, you have a problem with your back as a result of paddling your kayak, or fishing from it for long hours.
You ask your kayaking instructor, or your local kayak fishing outfitter for advice, and among several possible answers you're likely to hear some recommendations to improve your seat's lumbar support - either by adding foam somewhere (the DIY approach), or by getting a brand new kayak seat that according to its manufacturer is 'ergonomically designed' to offer 'improved lumbar support'...
Your local outfitter might even offer you a deal on a new kayak with a re-designed seat with improved cushioning, and guess what - you'll find a bunch of recommendations for that kayak (and seat) in online discussion forums that are sponsored directly (or covertly) by kayak manufacturers and other vendors of fishing kayaks and fishing gear...
What's wrong with this situation is that basically no sit-in or SOT kayak seat can offer any real lumbar support. This might seem as an overstatement at first read, but consider this
Your lumbar spine's natural support comes from your hip bones and legs, which in a natural active posture (I.E. walking, running) are placed directly below. This means your lumbar spine's natural support is vertical, and not horizontal. To understand why this matters, remember that your spine in made from bones (vertebrae) placed one on top of each other, and separated by thinner disks of softer cartilage.
In the L position, your kayak seat's backrest prevents your upper body from falling backwards, but it can do it only because your legs are pushing your lumbar area against it. Without your legs active push backward, your body would be slipping forward ('slouching').
In their turn, your legs can achieve this feat because your feet are supported by your kayak's footrests, which are placed directly in front of you - horizontally.
The bad news is that when your legs push your back against your kayak seat's backrest, the backrest pushes back with the exact force, according to Newton's third law of motion: "For every action there is an equal and opposite reaction."
The problem is (your problem, actually) that the backrest's reaction affects your lumbar spine from the wrong angle, continuously and with a lot of power.
In reality, your seat's backrest doesn't support your lumber spine - it pressurizes it from an unnatural direction, in an angle that doesn't offer your body a way to protect itself. This is why you feel discomfort, pain, numbness, tingling etc. - It's your lumbar spine crying foul, and warning you about potential problems developing as a result of the improper pressure applied by the seat's backrest.
So the truth is that the expression 'lumbar support' is a fallacy when it's used in connection with your kayak's backrest, since in fact such accessories don't offer support to your back's lumbar area - they just stop it from going backwards by brute force that your own legs are made to provide for this matter.
Those few lumbar vertebrae in your spine cannot support such abuse in the long run, and that's why you feel problems in your back... "