I ran the 2008 Chicago Marathon Sunday. It wasn't nearly as humid as 2007, but it was almost as hot: 65 degrees at the 8:00 start, 75 at 9:20, 79 by 9:30 and 84 by 11:00. Iwas confident I could run under 3:25 (my PR from a year ago was 3:23:53) and was hoping to run around 3:18, but I ended up at 3:36.
To reach my 3:18 goal I needed to run about 7:33/mile. I only clocked about 4 miles at 7:33 or faster. I was on pace for 3:20 through 16 miles but then I started to fade. I averaged 8:17 for miles 17-20, 9:39 for miles 21-23, and 10:00 for the last 3 miles.
I'm curious how other experience marathoners fared in the heat Sunday . What had you planned to run? What did you actually run?
I ran the Baltimore Marathon on Saturday the 11th. A have heard that there were many complaints about the day's heat, but I didn't think it was that bad (it got up to 76 degrees - warm, but not a major issue). It was certainly nothing like some of my training runs in July! I made sure to take fluid at each stop and I also grabbed a few bananas along the way (they are about 90% water and also have potasium) along with a few gels but I would have done that not matter what the weather. My time (2:48:22) was about six-and-a-half minutes off my PR, but that was mostly due to poor training because of injuries rather than the temperatures. My goal was to run under 2:50, so I was pleased.
I have run a couple of marathons in temps well over 80F. You have to train in temps that are as close to possible as your race for the best performance. But guessing what the temp will be is pretty tough. I usually do very well in cold climates and as such I try to train as much as possible in hotter climates in the event the raceday is a hot one. Also I try to train my long runs at the same time, if possible, when the marathon is. Many of the large city marathons go off pretty late - Boston 12:00, New York 10:00.
If you can get out to Philly for their marathon it is usually pretty cool and pretty flat. And you get the bonus of qual'ing for two Bostons instead of one.
Lastly, do not get discouraged! Running happens in the middle of life and sometimes you train for months only to arrive at the start line and have the temp way too hot, or way too cold.