Iâ€™m having trouble going the distance during VO2max intervals. I can generate the power, but I just canâ€™t seem to hold it. For example, in TrainerRoad I need to do 3 sets of 3x3 min at 108% (3 min rest) and 6 min rest between sets. I can get to 108% but then canâ€™t maintain it after 2 min, and later in the set I can manage 1 min but thatâ€™s it. (Same is true with higher %'s and shorter times.) Z4 stuff and below I have no problem with. It can be hard but I can complete it.
As Iâ€™m just a triathlete, not a roadie, Iâ€™m thinking I should just swap out the VO2max stuff for threshold work
. I figure if I can complete threshold intervals I will be training better than with a half-assed attempt at VO2max (assuming same TSS).
Does that make sense? Or will I be giving up a lot of performance trading Z4 for Z5?
Also, what might cause my trouble with the VO2max intervals?
- Am I just not trained enough at that level and I need to suck it up/use shorter intervals until I build that specific fitness?
- Is my FTP wrong? (I think itâ€™s pretty good. Itâ€™s based on a 20 min test, but it seems reasonable when I look at my data overall.)
- Is it just psychological? Again, I just need to suck it up?
My FTP is currently 251. Nothing awesome, but improving.
Don't do it man. Working those really high-end intervals (30sec to 2min) will pay huge dividends in how much power you can maintain during your threshold intervals. By the transitive property, they'll indirectly (if not directly) improve your FTP and race pace. And this is definitely the time of the year that you want to be doing those, assuming your races are predominantly toward the end of summer.
Edit: but yeah, based upon your difficulties here, I'd guess two things: 1) your FTP is biased high or 2) your high-end aerobic capacity is relatively inferior to your FTP. Remember, these "percent FTP for a given time" are just predictions based upon population data. And for that reason, we wouldn't place much faith in a 3-minute FTP test.