The Best Form Of Sugar During Exercise

It’s Q&A Day at 10almonds!

Have a question or a request? We love to hear from you!

In cases where we’ve already covered something, we might link to what we wrote before, but will always be happy to revisit any of our topics again in the future too—there’s always more to say!

As ever: if the question/request can be answered briefly, we’ll do it here in our Q&A Thursday edition. If not, we’ll make a main feature of it shortly afterwards!

So, no question/request too big or small 😎

❝What is the best form of sugar for an energy kick during exercise? Both type of sugar eg glicoae fructose dextrose etc and medium, ie drink, gel, solids etc❞

Great question! Let’s be clear first that we’re going to answer this specifically for the context of during exercise.

Because, if you’re not actively exercising strenuously right at the time when you’re taking the various things we’re going to be talking about, the results will not be the same.

For scenarios that are anything less than “I am exercising right now and my muscles (not joints, or anything else) are feeling the burn”, then instead please see this:

Snacks & Hacks: Eating For Energy (In Ways That Actually Work)

Because, to answer your question, we’re going to be going 100% against the first piece of advice in that article, which was “Skip the quasi-injectables”, i.e., anything marketed as very quick release. Those things are useful for diabetics to have handy just in case of needing to urgently correct a hypo, but for most people most of the time, they’re not. See also:

Which Sugars Are Healthier, And Which Are Just The Same?

However…

When strenuously exercising in a way that is taxing our muscles, we do not have to worry about the usual problem of messing up our glucose metabolism by overloading our body with sugars faster than it can use it (thus: it has to hurriedly convert glucose and shove it anywhere it’ll fit to put it away, which is very bad for us), because right now, in the exercise scenario we’re describing, the body is already running its fastest metabolism and is grabbing glucose anywhere it can find it.

Which brings us to our first key: the best type of sugar for this purpose is glucose. Because:

• glucose: the body can use immediately and easily convert whatever’s spare to glycogen (a polysaccharide of glucose) for storage
• fructose: the body cannot use immediately and any conversion of fructose to glycogen has to happen in the liver, so if you take too much fructose (without anything to slow it down, such as the fiber in whole fruit), you’re not only not going to get usable energy (the sugar is just going to be there in your bloodstream, circulating, not getting used, because it doesn’t trigger insulin release and insulin is the gatekeeper that allows sugar to be used), but also, it’s going to tax the liver, which if done to excess, is how we get non-alcoholic fatty liver disease.
• sucrose: is just a disaccharide of glucose and fructose, so it first gets broken down into those, and then its constituent parts get processed as above. Other disaccharides you’ll see mentioned sometimes are maltose and lactose, but again, they’re just an extra step removed from useful metabolism, so to save space, we’ll leave it at that for those today.
• dextrose: is just glucose, but when the labeller is feeling fancy. It’s technically informational because it specifies what isomer of glucose it is, but basically all glucose found in food is d-glucose, i.e. dextrose. Other isomers of glucose can be synthesized (very expensively) in laboratories or potentially found in obscure places (the universe is vast and weird), but in short: unless someone’s going to extreme lengths to get something else, all glucose we encounter is dextrose, and all (absolutely all) dextrose is glucose.

We’d like to show scientific papers contesting these head-to-head for empirical proof, but since the above is basic chemistry and physiology, all we could find is papers taking this for granted and stating in their initial premise that sports drinks, gels, bars usually contain glucose as their main sugar, potentially with some fructose and sucrose. Like this one:

A Comprehensive Study on Sports and Energy Drinks

As for how to take it, again this is the complete opposite of our usual health advice of “don’t drink your calories”, because in this case, for once…

(and again, we must emphasize: only while actively doing strenuous exercise that is making specifically your muscles burn, not your joints or anything else; if your joints are burning you need to rest and definitely don’t spike your blood sugars because that will worsen inflammation)

…just this once, we do want those sugars to be zipping straight into the blood. Which means: liquid is best for this purpose.

And when we say liquid: gel is the same as a drink, so far as the body is concerned, provided the body in question is adequately hydrated (i.e., you are also drinking water).

Here are a pair of studies (by the same team, with the same general methodology), testing things head-to-head, with endurance cyclists on 6-hour stationary cycle rides:

CHO Oxidation from a CHO Gel Compared with a Drink during Exercise

Meanwhile, liquid beat solid, but only significantly so from the 90-minute mark onwards, and even that significant difference was modest (i.e. it’s clinically significant, it’s a statistically reliable result and improbable as random happenstance, but the actual size of the difference was not huge):

Oxidation of Solid versus Liquid CHO Sources during Exercise

We would hypothesize that the reason that liquids only barely outperformed solids for this task is precisely because the solids in question were also designed for the task. When a company makes a fast-release energy bar, they don’t load it with fiber to slow it down. Which differentiates this greatly from, say, getting one’s sugars from whole fruit.

If the study had compared apples to apple juice, we hypothesize the results would have been very different. But alas, if that study has been done, we couldn’t find it.

Today has been all about what’s best during exercise, so let’s quickly finish with a note on what’s best before and after:

Before: What To Eat, Take, And Do Before A Workout

After: Overdone It? How To Speed Up Recovery After Exercise

Take care!