I PRed the 5K at the Charleston Distance Run a few years ago when it was 99 degrees and 99% humidity (ok, that might be an exaggeration, but it was easily the yuckiest race I've ever run).

Even at the 5k distance, when you aren't out there for as long as a marathon, it hurt way more than it should have.   I felt like I was dying.  Literally dying.   I had no business attempting to do that with that weather, but I had no real appreciation for what running in humid weather does to you.

That is all I have to add to this conversation.  

The 5K is pancake flat, but my husband did the 15miler that year  and he was looking AWFUL at the finish line.  Brutal.

My suspicion (maybe I'm wrong) is that it must hurt more to try to "race" a 5k in heat and humidity, than it is to race a marathon. Don't you need all your lungs at full capacity for a 5k? Without full oxygen, the muscles are not working well. It must be more problematic, no? Plus, people understand if we have to walk a little in a marathon. They are less understanding of runners who run 5ks, and then suddenly feel the need to walk. :-)

EDIT: I just reread what I wrote above and I sound stupid.  Ignore my comment.

onemile, what was the temperature is your last marathon recently?

 

Thanks for the clarification.  lol

LOL...

 

Why the one race in June? Not for the weather, obviously. The reasons are that it's on the way to where we are going for a week, on business. It's cheap. If I can run it in less than 3:42, I have a chance at winning first female overall. I like helping the local economy of places I particularly love (one night at a hotel, a couple meals, race registration). It makes me happy to run marathons.

 

Does that make me a merit badge collector? Perhaps. But... 14 marathons in 4 years, 13 of them in the last 36 months. That's more than one every 3 months. 6 of them I ran in 3:40 and less (BQ -15 and more), 6 of them I won AG awards for (4x1st place, 2x3rd place). There is at least some merit in the fact that I am not injured more often. :-)

Humble Brag alert!

Oski, you must be referring to 2012.  That was just stupid hot.  I have never in my life faded that badly in a race nor cared less about my finishing time.  I just wanted to be done.  I had a chance to talk to the female winner after the race and she talked about how horribly she faded.  Everyone talked about how horribly they faded.  Just brutal from start to finish.

 

So is it too slow a start if it's 65F? I need a sub-3:40, no matter the weather. 

I'm just saying this.

1.  If you don't discipline yourself at the start, you'll have to decide whether to take a non BQ or a DNF.  There won't be any other choices.

2.  As you run the race, your body heat will climb.  To make matters worse, as your body heat climbs, the outside temperature will be climbing.  On top of that, the sun will be coming out.  If there is no cloud cover, the sun will make it feel 10 degrees warmer.  There is a real risk of it feeling like 80 when you're at Mile 20.

3.  At the risk of restating the glaringly obvious, you can't run as fast when it's 80 as you can when it's 65.  Thus, if you fail to adjust your pace slower as the race progresses, you''ll end up walking.  You have to decide before this race ever starts, based on an hourly forecast, what pace you intend to run as the race develops.

 

I'm just saying this.

 

1.  If you don't discipline yourself at the start, you'll have to decide whether to take a non BQ or a DNF.  There won't be any other choices.

 

2.  As you run the race, your body heat will climb.  To make matters worse, as your body heat climbs, the outside temperature will be climbing.  On top of that, the sun will be coming out.  If there is no cloud cover, the sun will make it feel 10 degrees warmer.  There is a real risk of it feeling like 80 when you're at Mile 20.

 

3.  At the risk of restating the glaringly obvious, you can't run as fast when it's 80 as you can when it's 65.  Thus, if you fail to adjust your pace slower as the race progresses, you''ll end up walking.  You have to decide before this race ever starts, based on an hourly forecast, what pace you intend to run as the race develops.

YES to all of this.  If you do not adjust from the start, you'll suffer and be slower at the end.