It is a series of structured routines to do on the trainer or spin bike. There are five specific exercises that you work into a one hour indoor ride in various combinations over a 12 week period. The program is designed to build power more than endurance. So far I am pretty pleased with the results but I will know much more when I can ride outside again.

To make a long story short, you get on the trainer or spinner for no more than one hour with a specific plan in mind, as opposed to just pedaling along aimlessly for X amount of time. A HR monitor is very helpful in doing the program, as is a towel and water bottle. The legs are deeply sore and tired at the end of each of these sessions and rest days (or VERY easy recovery rides) are pretty much mandatory at our age. The program actually warns you against overtraining by using the workouts too often.