People always seem puzzled by vibration machines, at least that's what I've noticed at my local gym. They fiddle with the settings -- looking a little perplexed -- and then push the Start and either leap off with fright or stand and enjoy the experience.

But they rarely come back and even more rarely use the machines systematically.

The problem is that they don't know how, when and why to use them. Luckily for me, the gym keeps buying new machines to replace the old, and I keep using them.

Last night was an unusual one for me. My usually painful right knee wasn't painful.

I've been scratching my head all day as to what I had changed, and I've only come up with one thing.

The results seem too immediate. Could this simple change be associated with my pain relief?