How much Carbo?

Last Saturday I did my longest run since December 2008. Distance of 28km. It started off well and I was able to catch up with the front runners in my group even though I started about 5 minutes later than them. However, on the return leg, by the 22km along Changi Coastal Road, the energy level begun to drop and the pace became slower and slower.  I could see M about 50m in front of me but I couldn’t summon the energy to catch up with her. At the 25km outside NSRCC when she stopped for a drink at the choked water cooler, I ran past her but within 2 minutes she overtook me again and that was the way the run continued till the end with her finishing a good 5 minutes in front of me.

Fortunately for me, the run had come to an end. I knew if I had continued, I will hit the wall and come to a complete stop. I surmised what had happened was I had ran out of fuel or in cheem technical terms, depleted the load of glycogen stored in my body. How did that happened?

Let me see, firstly no carbo loading. In fact the day before, my entire day meal consists of a mishmash of junk starting with a small portion of fried beehoon, followed by another teeny weeny portion of abacus seeds for lunch, 2 slice of kaya toast and 4 tang yuen for tea and 1 bowl of laksa for dinner before wrapping up with a slice of peanut pancake for supper. How much calories are there in these foods? Personally I don’t think it was sufficient for me. According to HPB’s website, somebody like me need something like 2800 calories a day to maintain my weight so I figure best case scenario I took in enough calories to maintain my weight with no excess for the next day run. But this is at most guesswork.

Now some runner scientist in the US has come up with a specific formula to calculate the amount of carbohydrates required to run a marathon. To cut a long story short (you can read the summarized version here or the full paper here), one need to know his VO2 max (I don’t know mine which is a problem right?), expected pace; leg muscle mass and voila, take in the calculated amount carbohydrates and who knows you might be on your way to Boston!

For me, I think I stick to my short runs. It is so less complicated.