By Greg Searle The former Olympic rowing champion explains his role on GBR Challenge

Searle shows Sir Steve Redgrave the art of grinding

A grinder's work begins long before the race starts.

First we carry the sails to the boat. As each one is about the size of a tennis court, they tend to be quite big and heavy.

Heading out we have to grind the winches to get the boat out of the dock.

It takes about an hour for us to get out to the race course area and we use that time to have a briefing and get ourselves physically prepared.

I tend to lead the warm-up because I am the gym coach and, limited by space, we try to do the sort of exercises a rugby team might do before a match - a bit of shoulder rolling and swinging your arms around.

We have no Haka, but perhaps New Zealand will try one.

Our first job is to hoist whichever mainsail is selected.

And sometimes we have to hoist a man - our bowman Catflap - to the top of the rig to sort out problems.

In the good old day's they used to climb, but now we do all the work for them.

During a race, I am in the grinding position virtually the whole time, which means stood to attention by my handles.

I crouch on the floor out of the wind when I am not needed.

Occasionally, if a sail goes in the water, I might be asked to go forward to help pull it in.

But in America's Cup sailing we do not need to move around for ballast.

When we are performing a manoeuvre, the three boat grinders turn the handles as fast as they can and are joined by three others, who turn the same handles backwards to help us.

After a manoeuvre, I must set the gears on the winch for the next tack and set up the sheet (rope).

I basically see the trimmer as my customer, and whatever he wants I try to provide for him.

And if there is a situation going on where things are out of the ordinary, he is the first person I look to.

But as a grinder, I am definitely the lowest - the infantry - with the trimmers as sergeants.