Carb Concentration in drink mix

Sorry guys, this might be a stupid question but I couldn’t find it anywhere else in the forum. How would I measure the carb concentration in my Home-made drink mix. I’m working up to getting 100g of carbs per hour on the bike of strictly drink mix, so how much water should I be mixing with that? I have heard that about a 5% carb concentration is ideal, so how would I measure that to find out how much water I needed with the mix? Thank you all so much in advance.

Google is your friend :rofl:: Concentrations of Solutions

If I am reading what you are asking correctly, you want 5% of the content of your bottle to be carbs. This would suggest that 100g / 0.05 = 2000g of total amount of liquid. This may be imprecise, but 1g water = 1ml water. Convert ml to oz and you are looking at having a ~68 oz bottle. That is a very big bottle - normal ones are like 20-24oz capacity. You might want to spread the 100g across three 22oz bottles or change your desired carb concentration (to be higher).

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You don’t need 100g per hour…30-60g is fine unless you haven’t eaten anything that day. When I make up my sports drink - Wiggle own brand or High5 I use a 6% solution. Did a very hot 50m TT this morning in the UK - had a big bowl of porridge 3 hours before at 7am then 1 litre of 6% energy drink over the next 2 hours driving to the race and 450ml of 6% carb drink in the race…that said if my aerobottle had held more I would have taken a bit more as I was a bit dehydrated at the end :hot_face: but I wasn’t out of energy :grinning:

The way I see it, you can put any amount of carbs into a bottle, as long as it will dissolve and still pour out of the mouth of the bottle. As long as you have a second bottle of plain water / electrolytes to drink you should be able to manage the right mix depending on the temperature and your own specific hydration needs.

For example, if you’re doing a 3 hour ride and want to take in 300g of carbs, maybe put 200 in a bottle and take 3 gels with you.

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According to @Dr_Alex_Harrison 10-14% concentrations work best. Perhaps you can start with 100g carbs per 1L and see how that goes? Also, don’t forget about sodium.

Personally 14% has worked fine for me on the bike. During a run at the weekend I filled one 500ml bottle with a concentration of 40% carbs and used another 500ml bottle of plain water to chase down the thicker solution. That got me my 100g/hr and worked great.

The following threads contain some really great info:

There is also @Dr_Alex_Harrison’s book that contains lots of great info: The RP Diet for Endurance: Fueling, Hydrating, and Managing Electrolytes for Performance (Renaissance Periodization Book 8) eBook : Harrison, Dr. Alex, Howe, Michelle, Davis, Dr. Melissa: Kindle Store

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I tend to follow the approach of ‘put how much I want in the bottle and shake’ works fine. Did a long event where I had 300g of maltodextrin ans sugar mix in a 1l bottle! It’s was sickly sweet but hey, energy is energy. The other bottle was pure water to save my taste buds and teeth!!

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If energy gels work, why shouldn’t a 10% solution work? I am genuinely curious, maybe someone has an answer. Perhaps it’s not the optimal concentration, but I would think having a more concentrated solution would beat carrying 2 litres of water around.

The quantity of water In the mixture effects the rate of absorption of the carbohydrates. When these studies tout an ‘optimal’ concentration, it’s mainly a function of the body’s rate of absorption, not necessarily ‘more carbs are better than less’ claim

Ok, to rephrase my question, should I focus more on the absorption rate of the solution, or on the target amount of carbs? I can imagine that if an optimal rate of consumption is 90 grams of carbs per hour, and the concentration for an optimal absorption rate is 5%, does it mean I would have to chug 1,8 litres of solution an hour? That seems like rather a lot.

Would I be better off with less carbs at 5%, or with 90 grams at 10%? I understand that the quantity of carbs per hour is not fixed and could be less than 90 grams for lower intensity, but I focused on that extreme to make the question more or less clear…



This is dependent on personal training for tolerance, because the downsides if you overshoot the percentage for yourself, the results can be disastrous. ~7-8% is the often recommended safe concentration, start there and work up over a few workouts a week.

Here is a good way IMO to go about it

Training the gut

40:30 -

  • Being able to increase your gut’s ability to tolerate and absorb plenty of energy seems to be very trainable, especially for unexperienced athletes.
  • In order to get to know where your intake limit is, testing different strategies and relating them to performance and/or any levels of gastro intestinal distress is the recommended way to go.
  • In your preparations for longer distance races (typically the Ironman distance), it is absolutely paramount to getting your body and gut accustomed to your race nutrition strategy.

Ideally, your race nutrition plan should be practiced during sessions similar to your targeted race, this could for instance be a longer brick session at close to target race pace.

It is rather unclear if practicing taking in your planned race nutrition on more or less every single training session will have an additional effect.

  • I use to recommend athletes to target two sessions per week, starting 6 weeks prior a race where they focus very highly on their nutritional intake.

They start by for instance taking in 50g of carbohydrates/h and for each session they increase this number until they start developing GI distress, that is basically how much they can tolerate.

There are few things within sport that are, the more the better, but when it comes to carbohydrate intake during an endurance race, that is basically it!

I would start at 5% for a bottle an hour or something reasonable (ie lower amount of total carb). Experiment with increasing the % carb in the solution (more carb for same amount of liquid). You basically get an upset stomach or worse case diarrhea when you take on too much.

There is a line of training where they actually try to increase the body’s ability to withstand more carbs (with progressive overload just like your like training). Obv start low and work your way up tho.
Yes, drinking 1.8liter sounds crazy bc it is. Riding 100miles sounds crazy bc it is.

That’s why I say that applying training principles (on bike and for nutrition) that makes sense for elite/pro doesn’t always make sense for amateur/hobbyist. So do what makes sense to you and feels right. You will get performance benefits (from prob any amount of carb) but it’s not going to be a night and day difference even if you’re sustaining 100g/hr (it’s not epo)

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