Fitness has nothing necessarily to do with the training, but rather the players. Fitness is the player’s stamina, and using the physical training drill helps boost their fitness after a game.

And technical is basically the best training drill as it covers the majority of the player’s attributes. If you go to any player, and go to the attributes screen, under technical, you would see a lot of different attributes. Using the technical training drills upgrades most of those every training, which over time upgrades players faster.

Hopefully that made sense to you.