The videos below explain the rationale behind the program.
This will depend on your limiters. Here are a few thoughts.
This is often the number one limiter when athletes are trying to improve power. Address this and you'll see gains.
In this video, you'll discover the reason we are using your 4 minute power to measure progress. Keep in mind, the focus right now is not race day power. That will come later.
In the quest for improvement, many athletes push too hard when they should be holding back. If you find that race day power is much lower than what you commonly do on weekend training rides, then you are likely making this same mistake.
Strength is often a limiter for many triathletes. These low cadence intervals are ideal for developing your bike strength. Athletes with low force production will reap huge benefit from these interval sessions. As you progress in your season, these short intervals set the stage for sustained big gear intervals in the future.
While big gear intervals are essential for strength improvements, these high output, high rpm intervals help us develop the ability to turn the pedals at a fast while maintaining power. This gives us range as a triathlete.