I’ve had good luck with the ‘true lemon’ (https://www.truelemon.com/) crystallized lemon and lime for flavorings. Not as nice as some of the commercial offerings, but fine for a few bottles on the trainer.
Thanks so much for this information. I have been using the “homemade” mix with Nuun tabs for the last three weeks. I’m now finishing workouts that I have never finished and on my last Ramp received a 12% bump in FTP! So stoked.
4 Likes
I bought the true lemon and the flavor is “odd”. I can’t figure out the right amount to use in a bottle to get a good flavor. I agree that it’s great if you just want cheap, but I actually prefer the artificial flavors of the tablets. I recognize that probably makes me weird.
1 Like
We are all “weird” in our own way 
2 Likes
Hi, I’ve been looking at this thread for awhile now to make my own drink. I’ve used Maurten, SIS Beta Fuel, and also Tailwind. I thought that one of the benefits of the SIS Beta Fuel and Maurten is that they are isotonic, so that you don’t have to drink as much water for absorption and so that gastric distress is minimised while delivering a high level of carbohydrates.
Isotonic in the stomach. But when the Maltodextrin gets broken down into glucose in the small intestines it is no longer isotonic. And the small intestines govern the emptying rate of the stomach. It’s really all about the small intestines.
I use the High 5 stuff, it does the job nicely and if you can pick it up (UK) for £20 it works out at just under 50p a bottle. Tough to see how one can do much better than that.
2 Likes
Yep. It actually works out cheaper than DIY from Bulk Powders once you include flavour and isotonics. They do a caffeine version for the same price. I’ve just got one of each.
I hadn’t seen the caffeine version, I’ll give that a try - it mentions on the Wiggle product description that they’re in the process of rebranding, so I’ll load up on both before the price goes back up!
Bulk Powders often has 40% off. My glu/fru/electrolyte mix is about 10p per serving at the prices I paid.
1 Like
Certainly can’t beat those prices!
Could you comment on my understanding of osmolarity and associated GI distress?
- Hypertonic drink needs more water in the stomach to make it isotonic → stomach issues.
- Hypotonic or isotonic goes through the stomach into the small intestine or waits in the stomach
- Iso or even hypotonic in the stomach can be hypertonic in the SI (like lots of maltodextrine)
- Hypertonicity in the SI caused for example by maltodextrin break down is rapidly resolved by active glucose absorption and hence doesn’t cause GI distress by water dilution and not even by delaying the stomach emptying (why?)
1 Like
Can you expand on what this means?
Isotonic drink containing maltodextrin is broken down in the small intestine causing the osmolarity to rise and hence the drink becomes hypertonic there. But since it is broken down to glucose and there are active glucose transporters in the SI, I was speculating that the osmolarity doesn’t have to be equalized by drawing more water in the SI but by transporting glucose in to the bloodstream first.
The second part of the question was more on the cause of GI distress in general, because while the maltodextrine is being broken down and glucose absorbed the rest of the drink has to wait in the stomach. I wasn’t sure of the cause of GI distress - either very hypertonic drink (that needs to be diluted) or too much drink in the stomach.
Yes. Adding water to hypertonic will take it towards isotonic and then hypotonic. When talking osmolarity, there’s stomach osmolarity and SI osmolarity. Energy drinks market stomach osmolarity as their claim to fame, but it’s not the most important.
The more hypotonic a solution is in the stomach, the faster it will pass through the stomach except for the throttling the Duodenum (the first section of the SI) does on the stomach emptying. This is why osmolarity in the SI is more important. If the SI can’t process the drink solution a fast enough, it will slow/stop the stomach from emptying.
Yes. The malto gets broken down into glucose in the SI. The reason malto products claim a good osmolarity is because the molecule size of malto is small compared to once its broken into glucose. What they don’t say is that this is stomach osmolarity.
I may not be totally understanding this part but I’ll try. There’s 3 things we want absorbed. Water, energy (glucose/fructose), electrolytes. Glucose/fructose and electrolytes utilize active transporters meaning the transport rate is generally constant no matter what the contents of the SI are. Water utilizes passive transport which utilizes osmosis. Meaning for water to pass through the SI into the bloodstream, the osmolarity in the SI has to be lower than that of the blood. If the isn’t lower, water will go in the reverse direction from the blood into the SI, essentially dehydrating you. This is where stomach distress comes into play. Your SI needs some amount of water to keep distress from occurring. So there is a time factor as well. Drinking a hypertonic solution for an hour or 2, you will most likely not experience GI distress because you may have started hydrated enough that pulling water from you blood doesn’t bring you to that point in that amount of time (although could hurt performance). 4hrs+ and it could be a different story. This is individual too. Some people can go longer before causing distress. I wouldn’t think of the lines between hypotonic, isotonic, hypertonic as distinct lines either.
Keep in mind that most of this discussion is about glucose absorption. But water absorption has to be part of this discussion as well if you are riding longer than an hour or two.
3 Likes
Some water does travel along with the glucose/fructose and electrolyte active transporters. In my experience (n=1), GI distress has always been caused by not enough water in my SI. Anytime it’s happened, drinking a bottle of water immediately made it go away. In my opinion, it’s not caused by too much glucose in the SI (because that’s somewhat throttled by the SI anyways), but by too high an osmolarity in the SI caused by lack of water. Also keep in mind, when talking osmolarity you have to count everything in your drink, electrolytes too.
1 Like
Thank you! I was essentially trying to confirm if I understand the mechanisms correctly and tease out the reason for GI distress. If it is caused by water travelling in the wrong direction (body to stomach or SI) or by too much drink in the stomach (either because it had to be diluted for it was of a too high osmolarity or because it is waiting there until it can be continue to SI). I think you say it is the former.
And I know I was only focused on energy absorption. Electrolytes are not my concern outside of the hottest days as I don’t sweat out almost any salt. Water is obvious and I drink as much as I can which usually works ok. Moreover, I almost don’t race and certainly not for long durations.
1 Like
To be more specific, I don’t believe it’s just water going the wrong direction. It’s prolonged time of water running the wrong direction and you becoming dehydrated and the SI needs more water. It’s at that point in my experience that I have had GI distress. How long does it take? Depends on how hydrated you are at the start and how much the environmental conditions are reducing the water volume in your blood (sweating).
1 Like
I added SIS strawberry lime tab to that exact fructose and carbo gain. I had the entire bottle gone in 30 mins. That was sooo dang delicious. I could easily get in 180 g of carbs per hour with that recipe.
2 Likes
Thanks for the link, this is cool!
Here’s my isotonic recipe using Gatorade / CarboGain mix and US measurements:
18oz water
2/3 scoop Gatorade mix
1/3 cup Maltodextrin
Mixed in bulk in a drink pitcher:
1 gal water
1 1/3 cup Gatorade powder
2 1/3 cup Maltodextrin
On the most recent podcast they mention that new studies are suggesting that a 1:1 or 1:0.8 mix is more beneficial than a 2:1 mix. Has any determined exactly what the mix in Gatorade is? I’d like to try out a 1:1 blend.