Low Back Health - the Right and Wrong Information

This is wrong: 

When you do exercises that extend the spine, the vertebrae do NOT compress the discs as this picture suggests - quite the opposite.

Here is what really happens when you extend the spine:

As the spine moves into lumbar extension as in arching the back, the axis of rotation shifts to the facet joint which increases disc space in both the front and the back of the disc.

What's so good about this?

It relieves axial compression hence nerve impingement. As the muscles become stronger over time, permanent increases in the disc spaces are enjoyed and pain is greatly diminished or even eliminated.

So when your PT or MD says "Stay away from arching your back!" bend over backward to send them here!

Comments

[Kathy from Maine]

I'm re-reading all your blog entries, and this one hits kind of close to home.

I have an arthritic knee; almost all the medial cartilage is gone. The first surgeon wanted to rush into surgery to give me a partial knee replacement before he even knew what the problem was (he suspected a torn meniscus, even though neither the X-ray nor the MRI showed a tear).

The second surgeon wanted me to take it slower. He gave me a wedge to wear in my shoes that would raise the outside of my foot 1/4 inch, which he said would relieve the pain in the knee somewhat because doing so would open up the medial part of the knee joint.

It seems to have helped.

He also told me to do lots and lots of leg extensions with very little weight (like 5 pounds at most); he said any more than that would harm my knee. I said I preferred very slow squats, but he said that would harm my knee.

I know you don't agree, and would like to hear from you the scientific reason why you don't agree.

I have to say that I tried his "hundreds of reps with no weight," and it felt like I was wasting my time. Instead, I started walking in my yard (1 time around is 1/4 mile). When I started, I couldn't even get a quarter of the way around once. A month later, I could go around 10 times at a pretty good clip. It still hurts a bit, but nothing that stops me.

By the way, during that month I went back to doing my slow squats, too.

I agree with you that leg extensions don't harm the knee (even with heavy weights), but still would like to know the scientific reason why.

THANKS!!!