Other classes will take place in London and the South East, including in Bordon, Guildford, Reading and Alton, with details to be posted on the Facebook page.
The circuit-style workout included jumping-jacks, sit-ups, push-ups and partner work.
Helen left her job as a recruitment consultant two years ago to become a full-time fitness instructor and was inspired to become a naturist after visiting a nude beach in southern France.
I think I'm offering the first classes like this.