FIT is an excellent gym WordPress theme. It is specially designed for fitness, gym, spa and sports websites. It includes classes custom post type (with information such as difficulty level), trainers custom post type (with info such as contact, quotes, etc.) and custom template for trainers and classes.
This premium gym WordPress theme includes custom widgets for recent news, trainers and classes. You may choose between light and dark color schemes. The theme is fully responsive so it looks great on all devices. It includes a handy contact form.