Nate's Drop in FTP

Can we take a minute to talk about @Nate_Pearson’s big drop in fitness after his crash and recovery? Nearly 40 watts is so much! I lost the exact same amount this season after a small set back and taking a few days off the bike. Is this what @chad refers to as brittle fitness? I just can’t believe this many watts could be lost after months of consistent structured training.


For fitness to be ‘baked in’ takes years of consistent training at that level.


I find it hard to believe to lose 40w like that. At this stage we are getting into semantics of what FTP really means, which then is slightly worrying when basing training on these things.


Remember, measurements are just a snapshot at that instant in time. What you will be equally amazed at is how fast Nate will gain that back.


Some physiological components of FTP and VO2 (which if you are using a ramp to determine FTP plays a pretty big part) such as blood volume can be lost very quickly if you take time completely off the bike. But it will also come back fairly quickly. So most of the other mechanisms were most likely still there but because the ramp test isn’t really an FTP test but a MAP test then it will probably show a larger drop due to the larger and faster drop in VO2.


And then try it again the next day? This would mean then a ramp test once every 4 weeks is somewhat pointless exercise right? (unless we do it each day, which then is brutal!)

I would bet this is the anaerobic contribution to the ramp test number. What’s lost quickly, can be gained quickly.


I think they meant more like this test is not a good indicator of Nate’s overall fitness or depth of fitness. Rather it is just an indicator of where he was on that date after coming back from injury and time off the bike. Though your FTP will vary a couple watts each day depending on hydration, fueling, sleep, heat, fatigue, etc, etc. But that doesn’t mean you should test every day to find that exact number (which is another conversation but tests aren’t exact) but rather it’s something to keep in mind and don’t jump to conclusions about your fitness slipping if you could hold 100% FTP for 50 min last week but only 45 min this week.

As for testing every 4 weeks. It might be a pointless exercise for people who have been training for many years and are not currently in a huge build block were they expect to see massive gains. This is why you test every 6 during base but every 4 during build. But really experienced riders might only test every 8 weeks or more (especially during base) because an extra day of training will yield them more benefit than theoretically gaining a couple watts from a test.


Yeah, 40w is a big number, but his FTP was also HUGE. as a percentage, it really isn’t that much. What was he at…something like 330w? So it was a 12% drop in FTP.


I think was at more like 370 so he dropped down to 330ish. But yeah 40W at 370 is pretty different than 40W for someone at 200.


Yeah, best to look at both the raw watt change AND the percentage delta to get a fuller picture.


Hah…almost put down 370w, but I thought “nah…no way he was at 370!!”

I can’t even imagine that kind of wattage.


It’s not an unusual drop IME. I took 2+ weeks completely off last off-season, went from 272 to 245, a 10% drop. Nate’s was 12%.

I was back to 270 after the first base period. I bet he will get it back, though maybe not as quickly because 370 was a “new” high FTP and not deeply ingrained. I’d bet by the end of Base2 he’d be back up in the neighborhood again.


Couple things to consider:

  1. He initially had a pretty rapid rise to the number with few really good Ramp Tests where he was going head to head with Pete. So with a rapid rise perhaps not as surprising that it might also fall off fairly quickly.

  2. It would be interesting to know if 20 minutes tests done over the same period would have shown as rapid a rise and then as rapid a fall. I suspect a 20 minute test might have shown less of both an increase and a subsequent drop.


Could you please expand on this concept, I never heard about it and I could not find any reference to it in the forum or elsewhere. Thanks!

Is it just me or does this thread feel like talking about someone as if they’re not there?


To keep it short, endurance gains from high volume Z2 and tempo cause adaptations in your body that are ‘deeper’ and though they take longer to gain they also decline slower during a break or drop in volume. OTOH, gains from higher intensity such as VO2 (and some will say sweet spot) will come around much quicker but will also decline faster during a break.

Endurance gains are things like mitochondrial density, capillary density, shift to slower twitch muscle fibers, etc. while VO2 gains are things like rate of muscle recruitment and blood volume (a BIG one).


Seeing numbers like that, my gut reaction is that the ramp test isn’t measuring what it claims. Ramp tests are well researched and used to estimate Maximum Aerobic Power (MAP). Using MAP you can estimate FTP, but it is a range (not exactly 75% of MAP/1-min power) and then there is the fact you can’t precisely nail down FTP.

Interesting Cycling Weekly article published 5 days ago:

My personal highlights from that article:

  • Again, we must remember that physiological responses cannot be nailed down with pinpoint accuracy – thresholds are not black and white; the lines are always blurred.
  • The classic approach to test it requires several lab visits to quantify the lactate response to bouts of exercise lasting 30 to 40 minutes.
  • It is impossible to determine FTP with absolute precision. The measurement can fluctuate from day to day or test by test, and results can differ on the turbo trainer versus outdoors, especially if your room is too hot or you’re not feeling motivated.
  • Even in the World Tour, FTP has a mixed reputation. World champion Annemiek van Vleuten doesn’t bother to measure hers. “I also don’t care about it,” she says. “I train polarised.”
  • Lorang agrees: “FTP is easy to use, and if used in the right way, it can be a good tool for everybody, but we shouldn’t read too much into it.”

My viewpoint: I think people tend to overthink FTP and precise power targets.

see the second screenshot in this post:



I use the term “surface fitness”, but I think they represent the same thing.

It refers to fitness that does not have a deep endurance foundation to sustain it…even though you may achieve the same FTP, the “deepness” of the fitness is different. With a deeper base, you can sustain longer periods of inactivity without as much of a drop in fitness.

Here is the real world example I always used to give - Jan Ullrich back in the early 2000’s. he would always start the season overweight and end up having to “rush” his fitness for the Tour. He would drop out of races and then go train in isolation, looking to drop weight and quickly gian back lost ground.

He would arrive at the Tour “fit” with good numbers, but it was “surface” fitness (or “brittle”). Inevitably across the 3 weeks, he would have a “jour sans” because his fitness was not deep-rooted and had been rushed. Other riders (one guy in particular), who kept his weight under control and was able to train consistently would have the fitness and ability to recover that Jan lacked with his “surface” fitness.

Back in my late 20’s / early 30’s, I didn’t train very much due to family /work stuff. But we had a very spirited lunch ride at work (worked in the bike industry). So my training consisted of 3-5 days of the lunch ride and a few “longer” rides on the weekend (~90 min). I could get myself fit enough to race on weekends, but if I took a week off to go to Asia, when I cam back, my fitness would drop dramatically. Again, “surface fitness” only.