devashish_paul wrote:
JasoninHalifax wrote:
The 8 minute test isn't supposed to be purely aerobic. That's why you use 90% of that number as the Steady state aerobic number.
I know what you're getting at, but check your numbers. An anaerobic surge isn't going to skew the numbers that much. In an 8 minute test, 7:30 at 200 watts followed by 30 seconds at 300 watts still results in an average of 206 watts.
Put that same 30 second surge on the end of a 20 minute session at 200 watts and the average is 203 watts. Just a 3 watt difference.
Actually the more I think about the skew, I have had some athletes empty the tank during a bike test and spend the last 1 min hammering at 400W but closing the last 15 seconds at 800-1000W....that's when that final minute skews the results. Even if you take 90% of it, you are taking 90% of an artificially jacked up number from fast twitch component. On the other hand, if the 250W athlete spreads things over the last 4 minutes and rides them at 290W then that's legit part of their FTP as their undercooked the start.
I haven't done an FTP test since early summer but I did several between Oct 2016 and April/May 2017. My best 20min average was 303W giving an estimated FTP of 288W. I'm using that figure in the following example of how my FTP tests tend to go:
Before starting, I look at my last test and how I've progressed, or not, and consider what I think should be a reasonable expectation. In this case I think I should be able to average 298W or better.
First 2 mins: Aim just above expected average and maybe overshoot a bit:
305-315W. It starts off easy but I quickly start doubting my form.
2mins - 6mins: I drop a little but manage to hold onto an output around
295W -300W. I watch my early ~310W average start to subside towards 300W but remain determined I can stay close enough to 300W that my average will stay above 300W thus exceeding my expectations.
7mins - 11mins: I start to fade. Not halfway there yet and it's already really starting to hurt. My power drops first to the
low 290s and then even into the
mid 280s. My optimism was misplaced. I can't hang on. It's all falling apart. By half way point of 10mins, my average power has dropped to 297W. I start worrying I won't achieve my target and may struggle to finish the test with any sort of power left in my legs.
12mins - 16mins: I manage to halt the decline and start to drag my power back up into the mid 290s again but I'm suffering....a lot. My average stabilises around 295-296W.
17mins - 18mins: With the end starting to come into sight I find the will to add a few watts. I get back to 300W and hold it. My average is 296W.
19th minute: I smoothly accelerate from
300W up to about 330W. I'm trying but failing to block out all sensation from my legs. I'm gasping for air but the fact I'm able to raise the power acts as a painkiller. With a minute to go my average is up to 298W, my initial target!
20th minute: I debate whether I can last another minute at current power level. I decide I can. A few seconds later I wonder how my legs would respond if I release the safety regulators and throw everything I have at them. With 40 seconds or so remaining I attempt to surge again and get up to
380W. I try and hold it, and manage. With 20 seconds remaining I surge again and get to
400W. My vision is very blurred. My legs are agony, but my adrenaline is flowing. I both love and hate this point. A few seconds later I try one more time all out, no holds barred and get to
450W. The power almost immediately starts to fade. It takes a huge effort to try and hang on those last few seconds, my legs are either on or off, there's no real control. I just want to stop. I just manage to hang on as the clock hits 20mins. Blood hissing in my ears, my heart pounding, my legs aching, eyes blurry and my head spinning.
Average power 303W. New FTP 288W. That's how my FTP tests have all gone. I'll really struggle to go any harder early on but the last 2 minutes and the last minute in particular will make a huge difference adding maybe 7W total to my average over the 20mins and the last minute raises it all of 5W.
I tend to be the same in races. No matter how exhausted I am, I can always manage a surge at the end. In races the criticism I occasionally get is of course that I didn't leave it all on the course. I could have pushed harder. I shouldn't have anything left for a fast finish....well, I seem to have one extra gear that I just can't access any earlier. I don't think it's a psychological thing but who knows. To me it feels like it's all adrenaline and once I light the fuse there's no going back. One way or the other, I will have to stop entirely to recover after a minute at most. I do absolutely believe this makes my 20min average derived FTP significantly different than the value I might get if I did a true FTP test.