FreddyBoy

Background:
After any gym workout I've been incorporating a simple run on a treadmill.
I do 8-10 1min sprints with a 1min cool down in between.

Got a buddy who easily weighs 60lbs more than me that also did the treadmill.
My heart beat was 165 right after the sprint portion. He was sprinting substantially slower but his HBeat was 185,
I was more "spent" than he was after each sprint. (not quite to gasping but fatigued though I quickly recovered)

I cannot imagine being able to last @185beats/min for a full minute and am perplexed that he was able to do so.
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UPDATE: Just checked my max HBeat during a lifting workout. Somewhere during the workout I reached 195 and I wasn't even pushing all that hard for the most part.
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Anyway how this is all cycling related, is that I was trying to add a little something to a "gym" workout that incorporated a sort of interval. Help me with my sprinting on the bike.

Is this a lactate threshold issue?
Should I be trying to raise my heart beat/exertion during those intervals?

Hmm. Just doing some mental calculations:
A 200yd sprint
@30mph takes 13.63 seconds (recalculated to get the tenths correct)
@35mph = 11.68seconds (couldn't do that second one in my head :-)
Thinking maybe I should double up on the the running sprint intervals to 30 seconds and only allow a 30 second cool down.