4 rounds, each for time, of:
Bike 1 mile
Rest as needed between efforts.
Use a stationary bike or find a 1-mile course to repeat each round.
Post times for each round to comments.
Scaling:
Rest enough between rounds so that each effort can be performed at high intensity. Intermediate athletes can perform this as prescribed. Beginners can reduce the rounds and distance.
Beginner Option
3 rounds, each for time, of:
Bike ½ mile
Rest as needed between efforts.