Glucose to Fructose Ratio’s when fuelling under 90g/Hr

If you’re not aiming for optimum performance (eg less than 90g/Hr) is there any reason to do 1:0.8 Glucose to Fructose?

Ie if you’re doing 40-60g/Hr (for shorter rides or low aerobic rides) is there any science to suggest that 1:0.5 or 1:0.25 or simply pure glucose isn’t equally as effective?

Reason’s i ask;

Maltodextrin is cheaper than fructose
Fructose is sweater and (for me) less satiating.

Mixtures I’ve used (g).

30 malto 10 fructose
40 malto 20 fructose
50 malto 10 fructose
30-50g malto

Paging @Dr_Alex_Harrison

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Great question, I’ve been wondering the same thing myself as I’ll often fuel moderate 60min workouts with 30-60g/hr depending on how I feel and how intense the workout is.
I tend to use approx 1:1 or 1:0.8 ish.

My understanding is that you can only absorb ~60g/h of malto, so if you want more than that, you should top up via the other channel (fructose/liver).

I only use malto for shorter durations, as I also understand that fructose takes quite a while to be “ready to be used”.

use sucrose which is even cheaper. I’ve done 60g plain maltodextrin for a decade+, I liked it for a long time because its pretty flavorless. At that low of dosing there is no advantage to significant amounts of sucrose included, other than cost(from sucrose). I now use table sugar(sucrose) or powdered gatorade and try to keep the glucose around 60g/hr

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I don’t think you mean maltose, but rather maltodextrin. The latter is a complex carbohydrate polymer. Maltose is a disaccharide made of 2 glucose molecules bound together. However the interesting thing is that 1 g of maltose would have a lower osmality than 1g of glucose. Doubt it would make a big difference though.

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I meant to just type malto for malto dextrin but brain badly autocompleted. Thanks !

Cheaper options:

20 malto 20 sucrose

20 malto 40 sucrose

40 malto 20 sucrose

Similar sweetness. Same performance effect. Much cheaper.

Could also further double the sucrose contributions for the first and third option, reducing malto accordingly, achieve great performance, and cut cost. Only tradeoff is sweetness, as you mentioned.

Great question. Yes. 1:0.8 is cheaper than 2:1 or other ratios. 1:1 is cheapest. Pure sugar. :slight_smile:

But since you mention sweetness being an issue, nah, you’re fine with more malto at lower fueling rates.

Just sip steadily. It gets in and out of your gut and blood stream fast enough that if you chug 30g, and wait 30 minutes, off and on, you may periodically induce hypoglycemia.

Malto = Maltodextrin

Sweet. Do you see any disadvantages using sucrose over fructose? And by sucrose I assume you mean table sugar? Also does sucrose dissolve easily in cold water? Or is there a finer variety you use?


I’ve found no disadvantages. Shake well. Dissolves much easier than malto, too. Sucrose as in plain table sugar, granulated, yes. Powdered also works and is only 1% corn starch so might dissolve easier? Not sure. Haven’t bothered to use that instead of granulated. I just shake it up!