How much Slower did you run your 10k/HM in a tough Race Course and Setting?

Oh and the temperature was around 28 Celsius

I solo’d my half pr on a day with 30mph winds on mostly flat course. There are some calculators out there to help adjust times based on temp and humidity.

Years ago, I raced a lot of triathlons, and had a pair of races about a month apart that address your questions...both with a 10k run.

First one was at a ski resort in the Alps, with a mostly uphill bike portion and then a 10k on the up and down service roads for the ski area. My run split was 35:30.

About a month later, I did a flat race at roughly sea level. Run split was 31:50. Same effort

That's interesting.. I guess hills can cause most times a 3 minute difference and more if other factors come into play. Have you every raced on a real humid course? If so I would love to hear your experience

Not me, and not a 10K, but the course record for Mt. Marathon, a 5K distance, maybe even a tad shorter, is 42:xx, and it's been run annually for about 100 years, including some fast dudes.

Hmmm Would love to try that race atleast once. But am more curious about time differences caused by hills/weather for standard road races

Regarding temperature, my experience is:

5K; from 16:40 to 17:10 in 87 degrees humid.

10K; from 38 to 44 in 98 degrees dry.

Marathon: from 2:48 to 3:19 in 86 degrees humid.

From down Under wrote:

Regarding temperature, my experience is:

5K; from 16:40 to 17:10 in 87 degrees humid.

10K; from 38 to 44 in 98 degrees dry.

Marathon: from 2:48 to 3:19 in 86 degrees humid.

Wow that's quite a difference there between the 5k and 10k. Were these races done on a flat course?