It swoops through the air like a starved seabird. Aiming for the shell, it retreats dented. The creature inside the shell exhales a satisfactory sigh, rotates and drifts away.

"Is that what it's like?" I ask Robin Nash, Kateda Grand Master and believer in the Indonesian self-defence technique of Central Power.

"Is that what it feels like to withstand an iron bar blow to the chest?"

My question, I know, is desperate. But how else am I expected to understand how it feels to be able to punch iron plates, take bricks on the solar plexus, withstand strangulation and take simultaneous blows to the body -- and all without pain?

But it's OK. Robin is used to questions like this. At 32, he has spent the best half of his life practising Kateda and now, with classes running at Cricklewood's Production Village, it's time once again to open the door and therefore your mind, to the wonderfully deep world of Central Power.

"It's basically a form of breathing exercise," offers Robin, rather disappointingly. "It's learning to control the internal muscles so that you're able to take blows to the body. From doing that you can generate an internal energy and direct that energy to any part of your body. For self-defence purposes if you're blocking a punch or a kick you can direct that energy into that punch or kick."

So there's no pain, no injury? "I know a lot of people are amazed by that, but I have to stress the fact that you can't feel any pain. It's not that you cut the pain off or that you're damaging your body by cutting yourself off, because you're not. You're not actually feeling any pain from the blows."

Robin is on a roll. "If you practise Central Power it gives you a great deal of confidence. It's like you've got a shield of armour over you whereby if you got punched or kicked or whatever the case may be, to a degree, you will be able to withstand it. Obviously, if someone smashed you over the head with a hammer, you're not going to be able to withstand that. Hopefully you are going to try and block something like that."

If alarm bells are beginning to ring, it may be because of Kateda's allegedly shady past as sensationally exposed by the Sunday papers during the tail end of the 1980s which linked it to, of all things, cults. Robin is keen to set the record straight.

"Because we accept a lot of people who come from tough backgrounds there were some people at the time who were involved in training and management and they got back into the drugs scene. They were told to stop but took no notice so they were thrown out of the organisation.

"Once they were thrown out they went to the press and started the rumour Kateda was a cult and that there was all sorts of goings on -- drugs-related, sex-related, whatever you can think of basically, just to smear the mud over it. So since 1989/90 we've been trying to rebuild the whole organisation and that's been very difficult because even to this day that mud still sticks.

"But we feel we've got something very good to offer. I mean I was around in those days and everything that was reported in the paper, I can say I never saw anything of it. All I know is since joining it has never done me anything but good. It's never been something under the table. It's always forwarded my outlook on life."

For more details about Kateda call 0171 837 0739.

Converted for the new archive on 30 June 2000.Some images and formatting may have been lost in the conversion.