The players have contracts so they can play games. Default is 7 but you can add contracts which you can buy in the trade area. Every time a player plays a game they go down by 1 contract. Fitness has been removed for FUT 24 but exists in previous versions. Pre FC 24 it is gained by resting and lost by playing. Generally a player with 80 or lower fitness will be much slower in the game. You can buy fitness cards to add to individual players or to the entire squad.
![](https://i0.wp.com/www.girlgamervogue.com/wp-content/uploads/2020/10/contracts.jpg?fit=1280%2C720&ssl=1)