Advice on failed 2x20 AT test
 

Paging Koffee, DannoXYZ, et all.

Based on previous rides and observing my monitor the past few weeks, I guesstimated my AT to be around 160bmp which is right at 86.5% of maximum. I feel pretty confident that my max is 185 bpm. I have blown myself up several times and arrive on or just below this number every time.

Anyway, tonight I attempted the 2x20 AT test at 160 bpm and didn't make it through. The first 20 minutes I tried to hold at 160 bpm but would gradually creep up or creep down and I ended up averaging 161 for the fist 20 minutes ranging from about 156-164. After a 5 minute recovery, I picked it back up to to 160 but I jumped it up there too quickly as it only took me about 2 minutes to go from 115 bpm up to 160 and that pretty much wiped me out. I was able to hold 160 for about 7 minutes but started to drop and I bailed after 10 minutes with an average of 158 after the first 10 minutes of the 2nd attempt.

So my question is based on this account, can someone estimate where they think it probably is and does it sound like my AT is maybe a little lower than 160 or did I blow myself up running slightly higher than that on the first 20 minutes and not easing it back up slow enough during the second attempt. I realize this is just an estimate w/o a lab workup but am trying to identify the numbers I should use for steady-state rides, etc. Thanks for your input.

Do you have a datalog or graph of the events? There's usually a time-delay for the HR in response to power-output; kinda like a trailing moving-average with stock charts. You want to creep up to it gradually, don't overshoot and relax. The effort you're putting out on your legs should always be increasing gradually to dr ive up the HR, then you hold whatever effort is required.

On the 1st test, gradually creeping up and down while averaged 161 appears to indicate that your AT is actually higher than 160. The 2nd test may have failed due to muscle-fatigue that had you run out of steam, thus the lowering HR.

I would rest up and get plenty of rest and eat some energy bars no less than 30-minutes before the ride the next to ensure we're well stocked. :)

Question is, are you sure your max-HR is 185bpm?

Thank you. No datalog, just using an Polar CS100. At this point, I have to assume 185 is my max or atleast very close to it. I have done 3 separate Max HR tests on a hill near me. It's a gradual 5 minute climb that picks up steepnees towards the end and then levels out slightly before the apex for perfect out-of-saddle sprint. I hit 183 once and 184 twice so I am just rounding it up to 185. I was in some serious pain but it was my legs that gave out each time. I'll take your advice give the 2x20 another shot next week at 160 again. Some calories sooner before would help as I did start to feel a little weak at the end. I try not to stare at the HR monitor too much but i could certainly feel a change like I was working MUCH harder when i would creep up to the 163-164 range.

Ok, I think we're getting close. This test is a test of your aerobic system, so we don't want the muscles to give out too early. Try using one or two lower gears next time to save the muscles. This will let you modulate intensity a little easier as well by just changing RPM rather than trying to gauge pedal-force.

So try 2 gears easier than last time first, hold 90rpms for 15-sec and see what your HR stabilizes at. Then increase to 95rpms and hold for 15-sec and see what HR is. Then go to 100rpm, etc. At 110rpm, upshift up to the next gear and repeat. At some point, you'll home in on 160bpm... Gradually change RPM by 2-3 rpms at a time and creep up on the HR and do the 2x20 test.

Also try the treadmill running test for max-HR and you might hit 2-5 bpm higher on the max-HR. :)

How long was your warmup? And were you adequately rested before you did the test?

Koffee