Oh my God.

He's the Terminator, a former Mr Universe and a movie action hero, so there can't be

many personal trainers better than this guy. But lucky gym goers got at Gold's Gym in Venice,

Californina got exactly that.

You look like you're sweating a little. Let me just take care of everything. Here, have a towel.

In a viral video that went online this week, Arnold Schwarzenegger put on a dodgy disguise,

and posed as personal trainer called Harold Kleiner.

Keep drinking because we haven't finished the water drinking.

When it burns, it grows. Remember that.

You look so familiar to me.

Maybe you saw me on the FBI Most Wanted list.

You look pretty pumped up.

Remember we do everything in reps. So you've done two reps of water drinking. Usually we

do ten reps of everything, so another rep of water drinking.

Go down a little further.

You have elbows, and you have knees. So touch them. Very nice.

Stand up straight. Very good. Rep number seven.

Stop being a baby. This is Gold's Gym. It's not a baby gym.

And ten. Very good. You did it. Give me a five. Ow.

The prank was captured on hidden cameras around the gym. It was done to support After-School

All-Stars, a non-profit organisation that encourages childhood fitness.

Don't laugh. This is a serious business. The food supplements, the psychology of the mind,

the body. What's the most important thing? The weight training. That's right baby. Howard

is my name. Yeah, you have it.

Wow, you look so good. So handsome.