I had a back problem which I think was a protrusion ( is that what they call a slipped disc?) and did yoga stretches and also a bit of climbing on an indoor wall ( which made me realise how inflexible I was) and it really sorted it out. It recurred just before Christmas so I made an immediate bee line for the climbing wall which worked wonders. Don't keep the yoga and climbing up as much as I should though - they both really seem to have a preventative effect.