I tried out the Ride Live session, run by uber-enthusiastic Pierre Pozzuto, who has trained celebrities including Keira Knightly and Sarah Cox.
The combination of disco lights, banging beats and bongo drums meant I was having so much fun I nearly forgot I was exercising.
And then there's Reshape, which is a combination of high-intensity weights, floor work and running on the treadmill.
If you want to really feel the burn this one's for you.
The process involves a few minutes switching between sprinting and jogging on a treadmill, then weights and bench exercises, all while being shouted at by a trainer.