The Big Brother housemates have been given the chance to win themselves a special party with a sweaty Saturday workout.

Although they have been doing exercise classes every Saturday morning courtesy of Big Brother, this week’s came with a twist – they had to sweat as much as possible.

The housemates were given grey workout suits designed to show up the sweat, which were weighed prior to the exercise class.

After the class was over housemates had to return the suits, which were then weighed again.

They had to increase the weight of the suits by 50g in order to win a pool party – which will be held in the secret Pool Bar area.

And there’s an extra special treat in store for the sweatiest housemate – they will be rewarded with an ice cream sundae in the Diary Room.

See highlights from the workout in our photo gallery.

CLICK here for all the latest Big Brother news, pictures, profiles, features and fans’ thoughts