Lizzie explains that spinning is more physical than road biking
Spin at Fitness First Shred calories and improve your cardio in a 30 or 45-minute class. Membership starts from £18, nationwide.
Psycle A full-body workout with handcrafted playlists. £20 a class (or intro offer of two for £20), London.
RPM at Virgin Active An hour of hill climbs and sprints burns around 675 calories per class. Membership from £46 a month, nationwide.