While this is not a running product directly, back problems are prevalent, so I thought I would include this in my blog.
Having read lots of reviews, I decided it was worth getting a 'quality' product, rather than getting the cheapest available. If I am going to be suspended by my ankles, I figured I wanted to be confident in the quality of my support. The most highly recommended make is Teeter, so I ordered the EP-550 from Amazon.com for $299. (http://www.amazon.com/Teeter-Hang-Ups-EP-550-Inversion/dp/B0017LAORK)
The inversion table is heavy. If you have a back problem, you will need lots of help getting the table into the house and assembling it. The box is marked as needing two people to lift it, and they are not joking. Assembly is not difficult, but the instructions and pictures are not as clear as I would like. They provide a DVD with great instructions, but of course, I only looked at that after I was all done. RTFM.
The build quality is something I would expect to find in a gym rather than home equipment. The table is very solidly made, and everything moves smoothly and with precision.
The table needs to be setup for your height, so that you can control the inversion easily. The idea is that you raise your arms to change the balance point so that the table gradually inverts. If this is setup correctly, you can finely control your exact position. It took me a while to get this setup correctly. Being a runner with the 'T-Rex" build (big legs, tiny arms), my arms do not provide the same relative weight, but I still ended up with great control.
I was concerned that the ankle grip would hurt my skin, but so far I've not had a problem. Given the delicacy of my skin, I am tempted to try using the table with ski boots, but for most people, this should not be an issue.
It takes a while to get used to be inverted, as the blood rushes to the head. If you have high blood pressure, or other medical conditions, you should consult a physician. I find that I need to move to the inverted position slowly. I am expecting that my tolerance for being inverted will improve over time.
Being inverted helps my back significantly. I can massage the back muscles when fully inverted much better than in any other position. I have no problems with nerve compression, just muscular spasms, so I can't comment on how it would help that problem. I like the inversion table and I think it is well worth the money. It complements my massage chair (Panasonic EP3202) rather than replaces it. The massage chair is also an order of magnitude more expensive!
A recommended product.