This is a complement to the Sweet Spot Progression thread which is starting to fill with a discussion about threshold and VO2 (or all things coming after one completes an extensive aerobic phase).
When deciding how to structure my next phase of training that would come on the tails of completing an extensive aerobic block (mine was 6 weeks long) I decided that building power from the bottom up would be the next best step, followed by raising the roof (VO2 max work) which would help prep for an upcoming race.
I consulted this article by Tim Cusick to get an idea of how to structure my time @ LT2 né FTP/Threshold progression. TLDR: start with around 70% of your longest time at SS. If your longest SS session was 1x90, your first threshold session should target about 60 min of time at threshold.
That made my first threshold workout to be 4x10 @ 97-100% of FTP. It was challenging but entirely doable. Along with one steady-state threshold workout per week I’ve also included an over-under workout (that also progresses week over week) to get some time above FTP, but also continue to refine my system that buffers lactate. I also really like these workouts as a compliment to threshold workouts.
The progression would follow the same cadence as my previous SS block. 4x10 becomes 3x15 becomes 2x25 so on and so forth until I either run out of time and need to move to the next block or I’m able to perform 1x45 @ FTP*. Chances are I won’t get that far for this block, but nevertheless, the next 4 weeks should prove valuable in learning how to progress time @ FTP and prepare me for efforts that will likely be experienced in the upcoming gravel race season.
I had initially gone back and forth between a progression that favored longer intervals right at or just below (~10w) FTP or shorter intervals that were slightly above FTP (~10w), and ended up going with the longer intervals.
*As luck would have it I lost an entire week due to illness which threw a wrench into my 4-week progression. So now I’m crash-training with a big week in hopes to make up for the lost time. Ideally, I would have started my season sooner and given myself a good 6-8 weeks for a threshold build, but I’m trying to squeeze in a couple of week’s worth of high-end aerobic (VO2max) work leading into a pretty important race. (May races come too early!)