Never knew why, but when i try to use table or brown sugar, i cant use anywhere near the 100g / Liter / Hour in my bottles without getting nauseous. whereas maltodextrin +fructose 2:1 ratio i have no issues.
I guess that chart explains why.
If anyone enjoys Skratch Labs drink mix formula, i copied it and make it myself to save costs.
To make 1.0kg of mix
Maltodextrin: 666g
Fructose: 333g
Sodium citrate: 18.095g
Potassium citrate: 1.857g
Magnesium Citrate: 1.857g
Calcium Citrate: 2.109g
All ingredients can be found on amazon. For most of the citrates i use the brand “bulk supplements”
And then a standard food scale for the big measurements, then you need a jeweler’s scale for the potassium, magnesium, and calcium measurements
This thread has been super helpful. Thanks for all the great tips. I’m starting to compile recipes for gels , pre-workout, and recovery shakes. Feel free to contribute. I’m working on a few others but currently just have a recipe for SIS Isotonic gel in there. It’s super nice to get the same quality (if not better) product at a third of the price.
Reawakening this topic. Anyone have thoughts on using Glucose/maltodextrin : Fructose in a 2:1 ratio, compared with Glucose/maltodextrin : sucrose (some sort of table sugar, white or brown) in a 1:1 ratio? The end result will be the same ratio of glucose/fructose. But im struggling to grasp the implications of the lower osmolarity of sucrose compared to dextrose, and using sucrose/table sugar for the fructose source, will mean half the mixture has a lower osmolarity, whereas when pure fructose is used only a third of the mixture has the lower osmolarity compared to dextrose.
But i dont really understand what i’m saying… tried looking up osmolarity and it didn’t really help me/i’m too stupid to grasp the implications to sport nutrition.
I’ve started experimenting with table sugar, as i’m out of fructose powder. And i havn’t had any issues doing intervals, or with longer 4-6 hour rides. I’m kinda tired of paying almost $4/lb for the stuff. Whereas table sugar is dirt cheap, just like all the other ingredients. But i also dont really wont to go into a long 12-24 hour ride and regret my penny pinching.
Someone put all the Mixes of different drinks and gels on the forum. Very detailed. Maltodextrin and Fructose 4:1 and some sort of hydration mix for me
I used Maurten Gel 100 exclusively as my on bike food during Paris Brest Paris. I actually think it helped to settle my stomach after eating solid food at the controls; I’d feel a bit of an acidic burn after an hour or two and took a gel and it settled. I expect this is the sodium alginate - it’s also in antacids such as Gaviscon.
As I understand it, there are really 2 aspects to consider:
The mono saccharide ratio. 2:1 glucose:fructose seems to be about the number to target, especially when larger amounts are ingested. This same ratio can be achieved through a variety of formulations - glucose+sucrose, glucose+fructose, maltodextrin+fructose, maltodextrin+sucruse, etc. With the proper ratio of ingredients, the desired 2:1 glucose:fructose ratio can be maintained.
The osmolality of the solution, and in particular, the osmolality of the solution in the stomach. Here is where maltodextrin makes a big difference - since each maltodextrin molecule has many glucose molecules in it, the osmolality of a maltodextrin based solution with the same calories/liter is much lower than other formulations. Once the solution enters the small intestine, the maltodextrin is broken down very quickly into glucose. See the previous posts about how even long maltodextrin chains are highly available as glucose, and are not ‘slow’ to digest. Since the maltodextrin breaks down into glucose quickly in the intestine I presume this will also increase the osmolality, but I haven’t seen any literature on that.
My guess is that for many people glucose + sucrose will be fine for lower concentrations (it has been for me), but when pushing 100g/hour many will benefit from the maltodextrin. Maltodextrin is also not as sweet (relative to calories), so it may also help with flavor at the high concentrations.
I’m coming the end of my brought product, so ready to try my own mix.
I have a (flavoured) dextrose/ maltodextrin 50-50 mix, and fructose, so going for 666g/ 333g mix. I have premixed electrolyte powder.
My question is, I also use a powered multivitamin. Notwithstanding whether vitamin supplementation is effective in general - any pro’s or cons to adding it to the mix?
Don’t forget that maltodextrin has to be broken down in the stomach to glucose/fructose before it can be absorbed. With dextrose and fructose instead you get a faster mix and one that is more kind to the stomach.
Two things: maltodextrin is “absorbed as rapidly as glucose” and does not contain fructose at all, it’s just a long string of glucose molecules. So it will work just as well as dextrose, but like dextrose if you are looking to maximize your carb intake will need to be supplemented with fructose.
I have seen this claim but I’m not sure it adds up. As far as I can tell, the mechanism for maltodextrin being absorbed as quickly as glucose is that the enzymatic work of slicing and dicing the maltodextrin into glucose molecules happens relatively quickly, and has to happen before the glucose can be absorbed in the bloodstream. However, a solution of water and maltodextrin has lower osmolality than an isocaloric water and dextrose solution because it has fewer molecules.
So, either there are fewer big molecules reducing the osmolality of the solution (but the big maltodextrin molecules aren’t going to make it into your bloodstream to get used by your muscles), or by the time the solution hits your small intestine the maltodextrin and dextrose have both been broken down into glucose, yielding the same osmolality. Abstracts like Gastric emptying of water and isocaloric carbohydrate solutions consumed at rest seem to support the latter understanding.
This is my stance as well. Amylase is what breaks starches down into glucose. It only exists in the mouth and small intestines. Osmolarity is about moving things through a membrane, so to my knowledge has nothing to do with the stomach. By the time maltodextrin gets broken down and moved through the membrane of you small intestine, it is glucose. Any maltodextrin entering your stomach, exits the stomach as maltodextrin. So they claim that maltodextrin has lower osmolarity doesn’t hold water with me. Sure, in your water bottle and stomach it may have lower osmolarity, but not in the small intestine and that is where it matters.
Also Dr. Allen Lim (skratch labs) was the first to my knowledge to talk about osmolarity with endurance drinks. It’s interesting that skratch hasn’t switched to using maltodextrin in their drink mix instead of cane sugar and dextrose. Just another evidence point of why I don’t believe maltodextrin has lower osmolarity.
That’s because you are changing the osmolarity in your small intestine. If you mix it at the recommended ratio and drink enough to take in 90g/hr you would be ok. When I take in 90g/hr, 60g is coming from skratch mixed at recommended strength. Your not comparing apples to apples. Many get stuck on trying to get in 90g/hr, but neglect that the hydration has to be there first, or you will dehydrate yourself.
So we can just skip the water and just use sis isotonic gels?
I have actually tried this. My current setup is to get ~60g/hr from skratch and ~20-40g/hr from sis isotonic gels (I really like these gels). With this setup I get in 90-100g/hr and my hydration stays good. I’ve tried changing that makeup to ~30g/hr from skratch and ~50-70g/hr from sis isotonic gels. Was hoping this would work as it’s easier to carry gels compared to more water bottles. But a 3hr ride that I always finished strongly with the 60g skratch setup, I started to fail 2hrs in on the 30g skratch/hr. When I check my hydration, I was badly dehydrated.
I do understand these things can be highly individual, but the science says for calories to move through your small intestines, a greater amount of water has to be there compared to the water concentration in your blood. Otherwise it pulls that water out of your blood. Which is the definition of osmosis.
Gatorade gets its carbs from sucrose. So it’s 50/50 glucose and fructose. If you hit 90g of carbs an hour that way, you’re taking in too much fructose, which is generally associated with discomfort, flatulence, and feeling bloated.
On top of that, clearly whether it’s isotonic in the stomach (and the extent to which that does or does not impact gastric emptying) is not exactly the same as whether it’s isotonic in the small intestine, which seems to matter for blood uptake (of everything you are trying to put in… carbs, water, and electrolytes). Of course, the quantities of water and electrolytes that you are trying to replenish will depend on a person’s sweat rate, sweat sodium concentration, and conditions.
But if you compare Maltodextrin to Dextrose (glucose).
Moltodextrin has to be broken down to glucose and sucrose right?
Doesn’t that breaking down, take effort and time to get the same amount of glucose into the bloodstream at a given time?
While dextrose is already glucose in itself. And if you combine that with fructose you also get the benefit of the two together.
Made this mix over the weekend and tested a bottle on Sunday. I made it in a 1.6kg SIS empty, so added the dextrose/ maltodextrin, fructose (berry flavoured), and the appropriate amount of electrolyte.
Seemed to be ok both fueling, and was fine on the gut, but I’d be lying if it tasted as nice as SIS or Isostar. I’ll be experimenting with flavours - I have zero calorie flavour drops (including raspberry and strawberry), but will probably go with cordial. I guess this might explain the SIS/ aspartame thread.
It’s working out about €8 per kg for me here in Ireland. SIS currently have their 1 kg Go Electrolyte at half price at €14…