TLog: Blame it on the heat!

24 km long run, second attempt at making good the 3 km tempo run at the end. I was determined to make it this time.

Started out at 7 am with overcast skies, rain in the forecast. But the weather forecast was dead wrong, and the morning got hotter and hotter. First leg was uneventful, managed to keep 140 bpm cap at good pace (8+ min/km), and first tempo run was better than expected. Took a long recovery walk after that. About 250m for HR to come back down to 140, but it took a much longer time to come down to 135! I suppose this was the first sign of trouble. But I didn't think twice about it then.



Second leg was a struggle in the heat. Had to slow down to 10+ min/km to maintain 140 bpm. The last 24 km run in the evening was a cool affair, and I didn't have trouble maintaining at 8+ min/km pace. I knew it was going to be tough.

Sure enough, at 21st km, HR went up very high very fast. Hit 174/5 with the first km. Pace: 6:08, way off. The last run, HR was moderately high (about 160+). Not good.

Staring at the exposed, sunny and hot track (leading from NSRCC), I decided to fight another day. As it turned out, the temp reached 35 deg C (when I checked at 11 am, so at 10 am, it should be about 34 deg C)! No wonder I found it so tough! What can I say. I was disappointed. Simply not my day, and will attempt this another time.

Motion based had this wonderful feature that provides the distribution of distance by HR! So here's the breakdown:



Roughly eyeballing the distribution, the distance travelled under 140 bpm is about 40 to 50%, with the rest slightly over 140.

Here's a comparison of the Oct 7 and Oct 15 24 km run:

First leg: 7:04 to 8:22 pace versus 7:13 to 8:30 pace. About the same
First tempo: 5:45 (164 bpm) and 5:39 (168 bpm) versus 5:48 (171) and 5:43 (176). A little slower and higher HR
Second leg: 7:55 to 8:40 versus 10:14 to 10:49 pace. What a huge difference in pace!
Second tempo: 5:51 (167), 5:55 (170) and 7:19 (170) versus 6:08 (174!)

Clearly the weather/temp had a big part to play. In terms of hydration and fueling, there's no difference as I used powerbar electrolyte drinks (two bottles) and two gels in each run.

So what did I learn? That I don't do too well under hot temp (above 33 deg). I can run / jog slowly in high temp, but not at fast pace (especially after 3 hours). This is something to work on. :)