Friday, July 16, 2010

Heat and humidity; Training zones

Weather conditions during last night's tempo run:  89 degrees, humidity around 60%.  According to a heat index chart I ran across, that means it felt like 100 degrees. I know intuitively that heat affects running performance, but by how much?

I found a good article that has some info on how hot and humid weather conditions affect a runner. Here's some stats from that article:

  • Temperatures between 60-75°F will increase heart rate (HR) by 2-4 beats per minute
  • Temperatures between 75-90°F will increase heart rate (HR) up to 10 beats per minute   
  • Humidity levels between 50-90% will increase heart rate (HR) up to 10 beats per minute
If this is correct, that means the weather conditions last night could have increased my heart rate by as much as 20bpm. So, how do I adjust for this? 

Another article addresses the question of whether it is better to match the suggested HR (slower than normal pace) or match the suggested pace (with higher than listed HR). The recommendation is to match heart rate, but allow for a slightly higher heart rate that is about 5bpm above target. 

More on training zones:
This article recommends running easy runs at 60-70% max hr (The Energy Efficient or Recovery Zone); long runs at 70-80% (aerobic zone). I've been running both long runs and easy runs in the aerobic zone.  Maybe time for another adjustment there.

1 comment:

  1. Brian-being from Missouri, I don't know if I need to read the stats on temp and humidity and its effects on the body.

    I can feel it just stepping outside!! It is amazing how it just blows your body up. Its been hot and humid here this week and the last two days have been brutal.

    Just kidding on the stat thing--lets me know its not just me. Ha!! :)