Taking gels during training runs

my 2c wrote:

Trying to claim there's a difference between hitting the wall and exhausting energy in a marathon is playing coy. It's unfortunate you're not making an effort to hold a conversation, but you do you. Here's what you did say:

gels are a myth

Your original example was quite odd by choosing a 2:20 marathoner with a relatively high weight of 78 kg and with a vO2max of 48, which is quite low and would require the athlete to have extraordinary economy. If you start with a more likely 2:20 athlete - 68 kg and vO2max of 70 - and plug in the numbers, you would find, by your own math, that the runner exhausts his glycogen supply at 122.4 minutes, or over 3 miles from the finish line - not an unheard of time for a marathoner to slow significantly. (Also, note that Noakes doesn't use vO2max in his calculation; he starts with an average economy of 67 ml O2/kg/min instead.) Using Noakes's math, that fit 68 kg marathoner would have to drop to 62 kg - from 149.6 to 136.4 lbs - to extend the goal finishing time to 140 minutes, if there is that much weight for a 2:20 marathoner to lose in the first place.

So if you think gels are a myth, I'm not sure what your example was trying to show, since your math seems to clearly describe a fairly common class of well-trained marathoner whose glycogen supply will run out before the end of the race, and who would benefit from carbohydrate intake, as experiments and the experience of many athletes suggest.