Here in Hollywood I have joined a gym. Time usually drags while working out, but not in this gym. Every morning I get to see the most disastrous plastic surgery on women as they work out with their trainers in an attempt to look 15. It's like watching The Rocky Horror Show.

A very good-looking man comes every day with his two sons – one is 10, the other 14. Neither wants to be at a gym. The father is tanned, muscly and fit; the sons are both fat and pasty. This morning, the sons came in arguing with their father: "Why do we have to go? Can't we just run round the block a few times?"

I feel sorry for these boys. They are clearly happy being fat, but their dad wants them to be little action heroes. Ten-year-olds want the latest Xbox game, not biceps and triceps. They want to watch Arnold Schwarzenegger, not look like him.

All parents have expectations of their children, and some force their own dreams on to them. I was never forced to have liposuction or my hips implanted into my lips at 12, but I was expected to get a first-class degree, become a doctor and find a cure for cancer by 25. So I became a comedian, just to piss them off.

I bet those boys will binge on burgers for the next five years so they won't be able to move, and get the ultimate revenge – disappointing their parents.

• Shazia is performing her Edinburgh preview show at the London Welsh Centre on 18 June.