Sunday, April 10, 2016



IS YOUR CHAIR HURTING YOU?
 
by:  Mary Egbert PT, CLT, CKTP

Spinners sit...a lot….at times for hours on end and day after day.   We usually just plop down in our favorite chair not giving the type of chair we are sitting in a second thought.  Your favorite chair may be great for reading or lounging, but it may not be good to use when spinning.  If you are sitting in a chair that has not been correctly adjusted to allow for freedom of movement, correct body and joint alignment and optimum muscle use you may develop aches and pains or even injuries that can affect your ability and joy of spinning.  
Research has shown that prolonged sitting, especially in a slouched position,  may result in excessive loading and tissue deformation of the lumbar spine that can result in pain or even herniated discs. (1)   A poor fitting chair that causes ill-posture can flare up pre-existing conditions like sciatica or back pain caused by herniated discs.  You can also experience neck and shoulder pain, shin splints, leg pain or other ankle and foot issues.  If you have developed new  pains while spinning or your “old” pains are getting worse don’t blame your wheel,  it could be your chair and posture.   Let’s look at the chair you sit in most while spinning, you may find that you can do some minor adjustments that will do the trick.  
Seat Depth:     Compression issues common with spinners are at the back of the knee.  If the crook of your knees hit the edge of the chair you may be setting yourself up for a nerve  compression injury, also called a pinched nerve. Nerves work best when they are free to move. When the nerve is compressed by an external force this may damage or destroy the myelin sheath that protects and insulates the nerve. (4)  This damage reduces or prevents the movement of impulses through the nerve to the brain. This reduction of impulses or signals to the brain can cause symptoms that include numbness, "pins and needles" or burning sensations.   If the compression on a nerve persists you could end up with permanent nerve damage so it’s important to correct your seating now  to prevent damage.
The tibial nerve runs down the back of the knee  and can get compressed, or pinched,  from the edge of the chair. (2)   Compression of the tibial nerve can cause changes in the bottom of the foot and toes, including burning sensation, numbness, tingling, pain, weakness of the foot muscles or of the toes and ankle.   You can also experience compression of the popliteal artery that runs alongside the tibial nerve. Symptoms of arterial compression may be numbness, pain or cold feet, (3)    
To correct your seat depth place a pillow behind your back for support, scooting closer to the edge of the chair allowing about three to four inches of space from the crook of your knee to the edge of the chair. This decompresses the nerves and arteries giving the freedom they need to work at their best.
Walt Turpening, master chair maker for spinners and weavers, makes a chair that has a flexible seat edge that is curved to minimize pressure on the leg by the edge of the seat.
Armrests or no armrests:  If you love to long draw use a chair without armrests to give yourself room to move.  If you attempt to long draw in a chair that has armrests your elbows could hit the armrest as you long draw or you will be forced move in awkward positions.   If the body moves in awkward positions over and over again the stresses and strains on the soft tissue and joints will ultimately cause pain.
If you mostly spin short draw arm rests are ok, however, do not lean your elbows on the armrests when you spin.  This can cause compression to the ulnar nerve that runs along the back of your elbow, also called your “funny bone”.   Some symptoms of ulnar nerve compression are tingling or numbness in the ring and little finger, palm of the hand or pain in the forearm or elbow.
Seat height:  This may be different for every  body. If the seat height is too low it can cause pain in the shins or ankles over long periods of spinning due to the amount of muscle force it takes to treadle.   By raising the seat height allows for smoother treadling and less muscle force.  Give it a try, you will be surprised in the difference of treadling effort

How to measure for your correct seat height. (5)
  1. Measure from the floor to the top of the treadle, where your foot would rest.
  2. Put your foot on the floor and measure from your heel  to the back of your knee.  
Add those two numbers together. This is the optimum height your spinning chair should be.   If you don’t have an adjustable chair you could put leg risers under the legs of your chair to raise it up to the correct height.  Or get a piece of upholstery  foam and slip it into a pillowcase or make a pretty cover for it and sit on it to raise you up to the required height.
How close should my hands be to the orifice?
Let’s think about the mechanics of this for a second. If you were to spin with your hands close to the orifice, say about 2 to 3 inches away, you would essentially have to hold your arms up in the air.  This position would require a great deal of shoulder strength and stability to perform that task, especially if you spun for 30 minutes straight.  Try to hold your arms out in front of you for 30 minutes.  I don’t know about you, but my shoulders would quickly protest.  The ideal position would be to relax your elbows at your side with about a 90 degree angle at the elbows. Some even rest their hands in their lap when they spin.   Give this a try, your shoulders will thank you.
Sitting posture while spinning   Poor sitting posture, while doing any sitting activity, can cause a myriad of problems from neck, shoulder, back, leg pain, headaches or even muscle  fatigue and restlessness.  Poor sitting posture puts undue forces on joints, ligaments and spinal discs that can cause injury over a long period of time.
The most popular, but worst, sitting position is a slumped position putting the weight through the tail bone .  Note that the pelvis is rotated backwards.    In this position there is a great deal of compressive force  on the vertebrate and shearing force on the vertebral discs  that, over time, can cause pain and/or disc herniations. If you already have disc herniations  you should avoid this position all together.   The slumped posture  also causes a forward head position compressing the back of the vertebra in the neck and can ultimately cause pain or even tingling or numbness in the arms or hands.  
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Conversely if the low back is hyper extended causing the pelvis to tilt too far forward can also cause issues in the upper and low back  and muscle fatigue.


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The optimum sitting position would be with the pelvis in what’s called a neutral position, not too far forward (low back hyper extended)  and not to far back (slumped position).  Place a small  lumbar pillow at the small of your back to support your pelvis to maintain the neutral position.   This position allows the spine to maintain the normal curves without undue stress and strain on joints, ligaments, tendons and vertebral discs and will allow you to spin more comfortably for longer periods of time.
netural.jpg


Old timey spinning chairs vs. new timey spinning chairs


The old timey spinning chairs usually have a solid, wooden seat, no arm rests and a back that is straight as a board, literally.  Now I don’t know about you, but sitting on a piece of wood for even 10 minutes would be highly uncomfortable, not to mention the wooden edge digging into my legs.   The straight, wooden backrests are also very uncomfortable when you lean up against them not to mention they provide no support  or comfort for your back.  In fact you might walk away with a bruise-like feeling due to the apex of the curve in your thoracic (or chest) vertebra resting on the wooden backrest.  The seats are also very narrow and if you are of the wider-hipped persuasion the edges on the sides of the seat might dig into your hips.
One of the very few new timey spinning chairs are made by Walter Turpening who has been making custom fitted chair for spinners and weavers for over 16 years.  He  feels that form follows function, in that “seating for whatever purpose must fit the customer and made to position them comfortably”.   All of Walter’s seating designs are made to order to fit each person individually by taking various body measurements.  The materials used are cotton cord that is both comfortable and makes a flexible fabric that moves and gives with the user.
If you choose to adjust your current chair or invest in a custom made spinning chair, either way it’s important to use the proper seating to prevent pain and possible permanent injury from doing something you love so much. Once you are sitting correctly and are aware of correct posture you will enjoy spinning even more.
References:
1.  Wilder DG, Pope MH, Frymoyer JW.  The Biomechanics of lumbar disc herniation and the effect of overload and instability. J Spine
2.  www.netterimages.com/tibial-nerve
3.  Case report Popliteal artery entrapment syndrome
Ranjan Gupta, Nima Nassiri, Antony Hazel, Mary Bathen, Tahseen Mozaffar
Muscle Nerve. Author manuscript; available in PMC 2013 February 1.
Published in final edited form as: Muscle Nerve. 2012 February; 45(2): 231–241. doi: 10.1002/mus.22276
5.  Graciously shared by master spinning and weaving chair maker Walter Turpening
 
 




 
 
 
 

3 comments:

  1. Wow, Mary. This is so simple, but such good info. When I spin today, I'll check my posture. Sure don't need more back pain!

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