Jan Frodeno uses it. You could do a lot worse.
They reached out to me a while back and sent me a ton of it. I used it and liked it a lot.
The magic is the sodium alginate in it. Shake up a bike bottle of water with about a teaspoon of sodium alginate in it until it is fully mixed. That simulates what Maurten is before you drink it - watery.
Now pour it into a shallow clear tupperware bowl and then dribble spoonfuls of lemon juice onto it. The lemon juice simulates your stomach acid. Acid makes sodium alginate turn into a gel. In a short amount of time, the spots where you dribbled lemon juice will plump up into hydrogel lumps and you can scoop them out with a spoon. It's a really cool experiment.
Chefs have been doing this forever to make cool treats. Maurten is doing it to make your body see your fuel as more of a solid once it hits your stomach acid and it'll pass through to your intestines without irritating your stomach it like simple sugars would. Bonus is your fuel is literally encased in water, but I don't know if that's very helpful or just a little.
Here's a video showing how it's done. If you use calcium chloride instead of acid it does the same thing, so you'll see that in most video demonstrations.
https://www.youtube.com/watch?v=eKnlOgjdKWk
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