I jumped at the chance to get a free hotel room in New Orleans during Mardi Gras. But that didn't mean I was going to take it easy with my workout program. Today I wanted to do a little speed / distance work, so I decided on 40 minutes at marathon pace, then 5 at tempo pace, then 20 at MP and 5 tempo.
New Orleans is nothing if not flat, so I wasn't worried about terrain. I decided to define MP as 7:30 and Tempo pace as 6:30. What I didn't count on was the humidity. It was 70 degrees and 85 percent humidity during my workout. As I started warming up at an 8:15 pace, I could tell this wasn't going to be easy. After two miles, I tried to start building up to MP. I wasn't even close: My first mile was a 7:53. Four miles at 8+ minute pace followed. Finally by the end of the fifth "marathon pace" mile I was starting to get used to the heat, so I tried to turn it on for my first 5-minute tempo run. 6:30 was definitely not happening, but I managed a 7:00 pace for 5 minutes. Somehow I hung on for 2.5 miles at an 8:00 pace, then did another 7:00 pace for 5 minutes.
I was drenched in sweat and had underestimated the distance home, so my cooldown ended up being 3 miles for a total of 14. I was spent. The workout wasn't as fast as I had been hoping, but how did I do given the conditions?
Mark Hadley says you should add 0.75 percent to your mile pace for every 5 degrees above 60 during a workout. If the humidity is over 80 percent, add another 10 degrees to the temperature. So today it should have felt like I was running in dry, 80-degree weather. That sounds about right. That means I should add 3 percent to my planned speeds. At a 7:30 pace that would be 13.5 seconds, or 7:43.5 per mile. At a 6:30 pace that would be 11.7 seconds, or 6:41.7 per mile.
So no, even accounting for the weather, I still didn't hit my target times. But at least I wasn't so far off!
Details of today's workout are below.