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0 pointswging2mo ago0 comments

I've read that even if you absorb it all, there's some question about whether it's useful. This Alex Hutchinson article suggests, among other things, that it may spare your fat stores rather than your muscle glycogen:

> Even if you can absorb 120 grams per hour, it might not make you faster. In Podlogar’s study, cyclists burned more exogenous carbs when they consumed 120 rather than 90 grams per hour, but that didn’t reduce their rate of endogenous carb-burning—that is, they were still depleting the glycogen stores in their muscles just as quickly.

https://www.outsideonline.com/health/training-performance/en...

https://archive.ph/Vpk0h

https://pmc.ncbi.nlm.nih.gov/articles/PMC9560939/

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4 comments · 2 top-level

loeg2mo ago· 1 in thread

That may still be worthwhile if fat is harder to recruit than exogenous carbs.

wgingOP2mo ago

What does 'harder to recruit' mean though?

Earw0rm2mo ago· 1 in thread

Kejelcha is 6'1" and under 130lb.

What fat stores?

loeg2mo ago

It doesn't take much. If an elite burns 1500-2000 kcal running a marathon, even ignoring glycogen and exogenous carb, that's only ~195-260g of body fat (~7.7 kcal/g). Even at an extremely lean 4% body fat, Kejelcha would have 2360g of body fat available. (He's probably in the slightly higher 5-10% range.)

(And obviously, the majority of those 1500-2000 kcal are coming from stored glycogen rather than fat.)

If we're only talking about the marginal difference between 90 and 120 g/hr of exogenous carb, then that's 60g over two hours or 240 kcal -- equating to 31g of stored body fat. That's nothing.

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