I tend to develop bad lower back spasms-where my muscles knot up into a painful ball and my back between my shoulder blades becomes very sore and painful if I sew regularly.

I've gone to a chiropractor who helped quite a bit to get rid of the pain. but I want to be able to sew like I used to-several hours a night.

I can only sew for about 15 minutes before I start to feel the discomfort.

I've tilted my sewing machine forward some. Bought a sewing table instead of using a computer desk so it's lower, My chair is adjustable and I think it's at the right height.

I focus on good posture, block my core muscles so I'm not slumping and putting pressure on my lower back muscles.

What has helped you that I haven't tried?

I use the back weights that Clotilde sells. They are pricy @ $49 but I have used them for at least 15 yrs. Can't sew for more than 15 minutes without them. Often wear them all day long.

Have you tried a lumbar support pillow? I try to make sure my shoulders are down and relaxed when I sit down to sew. make sure your hands are at a comfortable level and don't slump your shoulders.

I had a PT show me exactly the best way to sit and sew so I wouldn't hurt. I sew sitting rim rod straight. I never hunch my shoulders or bend forward toward the machine. I only bend my neck down but never jut my head forward. My machine is sitting low. Bring your hand up until your elbows are 90º to your upper arms, that's the height your sewing machine needs to be. About the height of a pull out keyboard on a computer desk. I tilt the machine forward if I'm sewing for longer then a couple of hours. I took the back off my office chair and that's what I sit on. It swivels and rolls easy, even on carpet. I don't hurt anymore even if I sew all day.

P.S. I go to PT for exercise instead of a gym. I feel so much better then the hard work out I was getting from a trainer. I have better balance and feel limber. The exercises from the PT three times a week has made a big difference in my quality of sleep and how great I feel every day.

Also, it is important to move around occaionally... not a bad idea to stand and stretch every 15-20 minutes or so... Just stretch the areas of your body that have been flexed... neck forward? pull it back? shoulders hunched? go to the doorway and, holding onto the door jamb on either side, lean through the door, stretching your chest muscles. Hold stretches for at least 15-20 seconds. Don't stretch til it hurst... stretch til it feels good! Then hold that position for 15-20 seconds, minimum... Don't forget your hips... Stand up, keeping knee straight, slide foot behind you until the front of your hip is stretched...

Great book: "Stretching" by Bob Anderson

All these suggestions about the correct height for table and chair are very good!!

I have looked at a Posture Pleaser, but don't want to put money in another adaptive device that doesn't work, so when I had to FMQ last night, I put two 1 pound weights in a child's packpack I purchased for $1 at a garage sale yesterday. It seemed to help a lot. I also have a pads that angles my seat forward and a lumbar support on some chairs that need them.

Now how do you get rid of the leg spasms in the night after a stint of sewing?

My chiropractor told me that good abdominal muscles really help the lower back. He also said to stretch the back thigh muscles regularly(is that the hamstring? I can never remember.). According to him, those two things are very much responsible for lots of folks lower back pain and spasms. When these two things are not in good condition, the lower back must constantly compensate, thus causing it to over work and become stiff, painful, and & even to spasm.

Now that I'm writing all of this, I think I need to go do some crunches and stretching...

Your chiropractor is right!! Another great (and very easy, once you get the hang of it) "exercise" to strengthen your core muscles (your abs) is ... well, here's how I explain it to my therapy patients (whose average age is around 80 years old):
You know how when you "suck in" to button a pair of pants? That's your transverse abdominal muscle (TVA). The exercise is this... suck in your TVA and hold it in while singing a little tune or counting to ten or saying something, anything... the thing is you don't want to hold your breath. Tighten the muscle but keep talking/breathing... For fun, I teach my patients the "Mantra method." I have them repeat, " I... I, love... love, my... my, therapist!" Gets a laugh every time...
Do this exercise several times a day... when the commercial comes on... when the phone rings, when you walk past the refrigerator....
You get the picture..

I found that standing up while machine quilting is much easier on my back. I created a styrofoam "table" to enclose my sewing machine so I have a large surface to work on, and place the machine and the styrofoam on top of my cutting table. (Instructions for creating the quilting table are on Youtube.)

For piecing, though, I still like to sit down. I tried tilting my sewing machine but did not find that it helped. It's important that the machine be low enough so that the flat bed is about even with your bent elbows. I use a pneumatic height-adjustable office chair with no arm rests and sit as high as possible to achieve that. Many years ago I used the weighted back thingie from Clotilde, and it did help. However, I have not found it necessary since working out the correct ergonomics for my current setup. I do get up and move around frequently while piecing; I never sew sitting down for more than 40 minutes or so at a time without getting up and moving.

I should add that my doctor sent me to a back and neck pain clinic several years ago. I would go in twice a week and exercise, under their supervision, using equipment specially designed to isolate specific muscles that support the spine. After completing that program, I have had no major back problems and only the occasional tiny twinge. This was after decades of intermittent back pain including episodes where I could not stand up straight to walk.

I try to get up and move around periodically. My ironing board is on the other side of the room. I press at each stage. Sometimes I just have to get up and walk away for a few minutes. I have a wire mesh back support on both my computer chair and my sewing chair. I bought these at the Dollar Store. My sewing chair is a straight backed hard wood dining room chair with no cushions. Apparently, I come equipped with my own padding. :-)