The Cortana team has been rolling out new Interests to Cortana's Notebook for a few weeks now. One of them is the Lifestyle category, with Fitness Tracker as the particular class. (The other new interest is Showtimes + Trailers). Many of Cortana's characteristics and interests do not roll out to users all at once. Instead, Microsoft tends to push it out slowly, gauging feedback and usage. Lifestyle though is an interesting one: it appears that you can get the interest to show up by merely saving a favorite place as 'Gym'. If you are unsure on how to save places as favorites, follow these steps to get the Lifestyle interest in Cortana

How to enable Lifestyle and Fitness Tracker in Cortana Search for business/gym in Cortana Tap the name of the found business Tap the '+Star' icon near the bottom to add to Favorites Nickname the location 'Gym' It could take Cortana a few hours before the Lifestyle interest shows up. To check, just follow these directions: Best VPN providers 2020: Learn about ExpressVPN, NordVPN & more