Brady Holmer floats diet soda as a fasted training hack
The idea is a hypothesis he is thinking out loud about, and he says so himself.
Brady Holmer says there may be a way to keep the benefits of fasted training without giving up performance, and the trick is diet soda.
His argument runs like this. Putting something sweet in your mouth activates receptors that register carbohydrate as incoming. Artificial sweeteners, he says, are sweeter than most real sugars. So a diet drink hydrates you and might also switch on those same receptors while you are still technically training without fuel.
He posted it as a hack, then tagged the whole thing with his own "(maybe)".
What it actually means
This is a hypothesis, not a finding. Holmer does not cite a study in the post, he does not give a volume, a brand or a timing, and he does not claim the effect has been measured in runners doing fasted sessions. The "(maybe)" at the end is doing real work. Read it as a smart person thinking out loud on the internet, which is how he framed it.
It is worth separating that from the other thing he posted this week. Holmer also flagged a published study in which participants oxidized 40 grams of fat during a one hour run at fatmax intensity, the intensity where fat burning peaks, after taking 3 mg/kg of caffeine, against 33 grams without it. That one comes with a paper attached, and we covered it earlier. The diet soda idea does not.
So if you are the kind of runner who does an easy hour before breakfast because you like the way it feels, nothing here tells you to change anything. Nobody in the sources has tested whether a can of diet cola preserves performance in a fasted session, or whether it does anything at all beyond the fluid.
The reason the post traveled is that it sounds plausible and it is cheap to try. That is also exactly the kind of idea that gets repeated as settled a week later. Treat it as an open question until somebody runs the study, and take the number in the caffeine post, not the sweetener one, as the part with evidence behind it.
sipping a diet drink not only hydrates you but could activate these receptors to improve performance
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