Very hard, you will be in shape in a couple of weeks if you do a few reps every day.
Shoot a lay-up, grab it out of the net then back peddle to the half court line, then turn around and sprint to the opposite baseline. Then back, get the ball and put it back in. Do this 10 times in 1 minute. If there are to players when the player doing the running is at the opposite baseline the other player will pass him the ball and the runner will dribble it for a full court lay-up
Leg strength, long lasting conditioning.
1 player to 2 players.

The basketball drills are licensed under a Creative Commons License.
TLC: Pål Degerstrøm 2000-2008