Right, on the mega website it says that only elbow pads are needed.

i'll be wearing some knee/shin's for good luck, but would people reccomend something with a bit of back protection?

I'd want a Zorb.

And some of that foam isht from Demolition Man

Just remember that at the start there's a very real chance of being run over if/when you fall, so I'd recommend all the armour you can get ...

I've been told it's actually quicker to lay on your back, holding your bike behind your head, and slide down the first bit instead of riding. So yeah maybe a Spine protector with a ski on it

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