What race are you most likely to hit your Max HR in?

Given that vo2 max generally corresponds to an effort of 6-8 minutes, I'm gonna say 3k (if you're fast) and the mile (if you're not).

400, 800, 1000m aren't long enough for your heart rate to "catch up" (for lack of a better term). These events rely very heavily on the anaerobic system, and heart rate is a proxy for aerobic output.

2 mile (~8:00 for an elite)

Then 3k (~7:25)

Not sure how accurate it was, but my highest recorded HR ever on my watch was set in the last ~600m of a track 5000m race where I hit 204.

I think that intuitively though, 3000m makes the most sense.

Never ran a 3k, but the last time I ran a 5k I was at 95% of max HR at the mile mark. Didn’t check my HR for the rest of the race, but it felt like I was redlining from the gun.

For me, it was the end of a half marathon in Aug....misread the finish line

This is the correct answer. For an elite it may as well be a 5km as even a 12-14min race for a very experienced runner would probably be close enough. (Elites can hold 100% Vo2max and therefore about 100% max HR for several minutes at a time essentially).
For most probably a 3km....
Here're the kicker though: You have to pace it perfectly and get everything out of yourself! (pretty even splits to maybe a very slight negative split effort).

I feel like it can also happen in most races if you finish with a long, fast close. I only have had a handful of races run with a HR monitor, but I've reached my true/real world max of 181 in both a short (5Kish) trail/xc race as well as a marathon.

I agree.

If you've paced a longer race well enough, and you aren't limited by a lack of musculoskeletal durability and/or fatigue, then you should be able to reach vo2 max at the end.

It would probably also help if you were in a close race with someone else, and there was a bit of a hill to finish.

The 1500 for me.

I always went out too hard (trying to run with faster teammates) and felt like about 800m into the race I was complete blowing up. By the last 200m and my attempted "kick," I was dying.

I was not any good at the 15, but I raced it a lot and it was always super hard for me.

Read this three times, then looked back at the thread title, then laughed out loud.

Same. Not sure if there is a sexual connotation either.

I’d bet it’s much shorter for people who aren’t trained endurance athletes. Like 400m.

On the track, run as a time trial, it’s probably the 3000m. As others have said, that will depend on your fitness level and how long that race will take you.

Based on my experience cycling, the times where I have seen the most eyepopping HR numbers out of myself were repeated anaerobic efforts at the end of a race. Like a very hard 30sec effort to shatter a group on a hill shortly a minute before the end, then back to a high aerobic pace before a long hard sprint to the line. This kind of effort is rare in running but you’d have something like it with the right hills at the end of a hilly road or XC race. Come to think of it, the last time I saw my max HR was at the end of a hilly finish to a road 10km…

I agree, im not saying the 3k folks are wrong, but if you cant get to HR max in a 1500, you are not doing it right. the CV delay isnt more than a lap or 2 at most. 4-5 min of running with blinding effort and pain will get you there.

A good 1500 is only 3.5 minutes...too short

Didn’t they have heart rate monitors on the guys at pre classic and nguse one said 200bpm in the homestretch of the mile?

And...? Maybe that's his max, maybe it's not. The heart rate numbers they show on broadcasts are pointless without context. As are the gushings on here like "Grant Fisher ran 18 miles at altitude at 5:40 pace and his average HR was only 143."

It’s a well run mile.