It’s a log scale for time and just how similar is similar could be debated, but, yeah, pretty much.
I’ve seen a graph of the correlation of FTP with power as a function of duration - I will see if I can locate it. IIRC, though, FTP explained more than 90% of the variation between individuals from a few minutes onward.
Are you familiar with any studies comparing MLSS and RER? Curious if they differ much among athletes
I know that sometimes people try to identify or define LT based on when your RER reaches 1.00. I don’t think that things are that closely connected, though - for example, somebody on a high fat diet or just really well trained would probably hit threshold while still oxidizing a measurable amount of fat.
ETA. Found this study of runners. RER at MLSS was 0.88 +/- 04 in men and 0.82 +/- 0.02 in women.
Yeah that’s the one I saw too. And this study on men found an RER of .94 before and after training but also having a longer TTE. So same carb/fat oxidation but for longer time.
Now I’m starting to wonder if LT1 is the driver for rer@threshold
I guess it makes sense, that is why the FTP tests work so well.
Super interesting and useful. Especially if you can correlate RER to VT1 and VT2. Based on another research document, I’ve guestimating ~50/50 (RER .85) carbs to fat consumption at a steady-state workload.
https://www.sciencedirect.com/sdfe/pdf/download/eid/3-s2.0-B9781416031970100692/first-page-pdf
Let me clarify. Yes. The general trend of how sustained power decreases overtime is generally the same. However, the amount of power one can sustain at VT1 and/or VT2 is not solely based on FTP (using a 20-minute test), and is more of a function between aerobic strength and anaerobic strength… that’s my point. This is because some athletes’ strengths are aerobic and others are anaerobic. If your anaerobic system is very strong, then much of your high FTP is a result of your anaerobic gift. Basically, the relationship between power output across VT1, VT2, and VO2MAX can vary between athletes.
Why this is important… because I’m not simply interested in my FTP. Other than using it as a training marked (I’m actually currently using my Lactate Threshold), it has very little meaning to me and to my performance during a 5-hour event. FTP comments these days seem analogous to “how much can you bench press” questions from high school. There more to cycling success than your FTP.
Does it not depend on testing methods? 60 min test has minimal anaerobic contribution, ramp test - high.
“Several attempts have been made to predict endurance ability of the athletes, particularly in continuous events like long distance running. Farrell et al (65) reviewed that the anaerobic threshold yielded highest correlation (r = 0.98) with marathon running performance. Kumagai et al (66) observed a higher correlation between 5000 and 10,000 meters running performance and lactate threshold (r = 0.95 and 0.84) than between running performances with the VO2 max (r = 0.65 and 0.67). Sjodin and Jacob (67); Karlsson and Jacob (68) related 4mM/L (OBLA) lactate to endurance performance and reported a high correlation between them (r = 0.96). It is very much evident from the earlier observation that in elite runners, the onset of blood lactate accumulation (OBLA) occurred at a higher running speed (65, 69, 70). Besides continuous events, the importance of anaerobic threshold in non-continuous intermittent games has also been discussed (40, 71, 72).”
From: Anaerobic Threshold: Its Concept and Role in Endurance Sport - PMC).
I’m sorry, but that is simply incorrect.
ETA. I found that chart I’d mentioned before. Even at 5 hours (18000 seconds), the correlation between average power and FTP is still around 0.9.
What does an undergraduate chapter about VO2max have to do with your statement above?
Sorry. A chart without the study and research method doesn’t prove anything. Who were the subjects? Were they aerobically developed or simply strong anaerobically. Assuming it’s true, then 10% difference among aerobically developed athletes is actually pretty substantial.
Yes. Test method matter. I mentioned the 20-minute format in previous comments.
It’s something that Coggan posted when WKO4 came out. The power data are from the couple hundred athletes he used to validate his model. IOW, not a lab study, but more like the sort of data that TR would have.
That would add some variability, but even estimated that way FTP would be a better indicator of your 5 hour power than any other measurement.
Keep digging, though!
ETA. I notice that you haven’t addressed the studies @jarsson posted about?
It involved runners not cyclists. Very different and I have little interest in it.
Also, a couple of important words in my original statement, “… very little meaning to me and to my performance during a 5-hour event.” Notice I say “my performance.”
I’ve been down this road before. Two years ago I thought I was in the best shape of my life. My FTP was 4.1 w/kg (based on my 20-minute power). I got to this point by spending 10 months doing nothing but 2x20 at FTP and 5x5 at 120% threshold. I had conditioned myself for 20-minute efforts. The last 5 minutes of my 20-minutes test was over 130% of my resulting FTP. That means 25% of my test result was due to my stronger than average anaerobic capacity. However, the problem was I couldn’t sustain 80% of my FTP for 60 minutes because I hadn’t developed the physiological adaptions needed for longer efforts.
Last year I had to do a reset. I’ve been working to improve aerobic capacity. That’s my current focus and why I really don’t care about my FTP (other than for training zones). In fact, I’m actually using my LT to set my zones (both power and heart rate). While my current FTP is 11.5% lower than before, I can hold a much greater amount of that power for 120 minutes.
I had to learn the hard way that Threshold and VO2 efforts are better saved for 6-8 weeks before an “A” event. The majority of my training now is SST.
I do not want to tell you what to do as apparently you are doing great but if you have been doing 2x20 no wonder you have not developed extensive power as you have been not training it. TTE is a very important part of your FTP. Z2 + extensive FTP will do the same job. My 2c.
Example (for 73 kg):
Something is wrong there.
The fact that you chose a test that clearly overestimated your FTP then trained to that test doesn’t change the fact that yes, you DO care about your FTP - you just refuse to accept reality.
Where does this idea come from?
FWIW, #1 on my list would initial glycogen stores.
That would be my #1 as well
Looking at a couple of the studies linked above. The masters runners extended TTE without changing RER.
Obviously as time increases, total fat and carb oxidation increases.
So lets say you always start with topped up glycogen stores. All the carb intake in the world during the effort wont increase TTE all that much, I can’t slam Gatorade during the effort to increase time by 10min . It’s not like glycogen stores always go to 0 after an exhaustive effort anyway.
This study here experimented low CHO availability
TTE was unchanged below LT2 between 10% carb diet and 65% carb diet.
Of course things above LT2 are different. High carb won.
So what else is left?
The ability to oxidize fat, and fatigue itself.
Thoughts? Am I making too many assumptions?