94% max HR for 38 min ?? (good or deadly?)

[Alex Simmons]

True, after a few minutes in any interval above threshold power, my HR will start to reach my max, but is it really possible to be at 90% max HR and have 75% of max power left to really sprint at this point?

Yes - ever raced a crit or a points race? 90% of max HR ain't that big a deal in a hard race. Max HR and Max power are completely unrelated.

Sprinting power is independant of MAP, and if you are already at 90% max HR, that means you've got little room to extend and I think it would be impossible to sprint at your max sprint power at this point in time. Sprinting power is only attainable from a relatively light start, not when the body is already stressed and working anaerobically as it is at 90% max HR. I think he also mentioned it was in a race type situation, which makes it more valid.

Well it's either independent or it's not - which is it? You can't say it's independent and then claim one impacts the other?
I set a new PB peak power last year at the end of a hard race where I was thumping out higher than threshold average powers and high heart rates.

 

[ZimboNC]

Sprinting power is only attainable from a relatively light start, not when the body is already stressed and working anaerobically as it is at 90% max HR. I think he also mentioned it was in a race type situation, which makes it more valid.

I don't think this is true. I've only finished one crit in my life but my anecdotal evidence contradicts your statement. I was in a solo breakaway for the last half lap. My heart rate approaching the final turn was at 97% of my recorded maximum (191 bpm, highest ever recorded was 196). Due to a mechanical problem (extremely loose stem bolts that turned my handlebars into a wet noodle), I was unable to stand up to sprint at the end yet I was still able to average 750 watts (max 800) over the last 14 seconds of the race. I believe I could have hit 900-1000 max watts if I'd been able to stand and I'm no sprinter. Since my FTP is around 300 watts, you can see that the 35% number isn't far off.

--Steve

 

[jeff828]

Originally Posted by K50
This is so wrong it's not even funny. How can you be at 90%MHR and only be at 25.9% of your max power. That's humanly impossible. You cannot show me one person in this world who fits that criteria.

Err, you might want to think about this one a bit.

Go and ride a VO2 Max interval or 3 and I bet after a few minutes your HR will be pretty well up near your max. But power output at VO2 Max is (for me anyway) about 25% of my maximal power output in a sprint. My heart doesn't (can't) beat any faster in a sprint though...

WOW. very interesting, I just did Vo2 intervals tonight 5x2min, @290watts & HR @190. I came home & read this so I took out the calculator & it sure enough it matched EXACTLY what you just said Alex.

Ave sprint 1200ish x 25%=300watts
Max HR 210 x 90%=190

I rode 90%MHR @25% of max sprint

So I did exactly what k50 said was impossible, math is sometimes interesting or was this just a coincidence?

 

[Alex Simmons]

So I did exactly what k50 said was impossible, math is sometimes interesting or was this just a coincidence?

A coincidence. Everyone's power profile is different, some can sprint, other can't. Max HR and Max power are not related in any way so don't go drawing any conclusions based on relating the two.

 

[K50]

Originally Posted by K50
This is so wrong it's not even funny. How can you be at 90%MHR and only be at 25.9% of your max power. That's humanly impossible. You cannot show me one person in this world who fits that criteria.





WOW. very interesting, I just did Vo2 intervals tonight 5x2min, @290watts & HR @190. I came home & read this so I took out the calculator & it sure enough it matched EXACTLY what you just said Alex.

Ave sprint 1200ish x 25%=300watts
Max HR 210 x 90%=190

I rode 90%MHR @25% of max sprint

So I did exactly what k50 said was impossible, math is sometimes interesting or was this just a coincidence?

Yeah maybe I just suck at sprinting

 

[BullGod]

i think the difference is whether you take max 5 sec (sprint) power or MAP.

I think if you take MAP there is no way you could be at 90% of HR max at 25% of MAP. For me that would be 160 bpm @ about 100w!

I usually aim to do 30 min intervals at 90% of HR max - and I do those at 370w, which is about 85% of MAP.