The Calorie Confusion – Can you run around the world with just water and a tube of effervescent tablets?

Can you run around the world with nothing more than water and a tube of effervescent tablets? That’s the question we are going to try to answer today!

Recently, one of my athletes remarked that an effervescent tablet she was taking was very calorie rich and so she was averse to taking it.

Now this tablet is a typical effervescent tablet: very small, hardly weighing 5-7 grams. She said the nutritional label on the tablet box said each tablet contained 13kCal (thats 13 kilo calories or 13000 calories). She said when she runs 10K, she burns about 700 calories, and so was worried about taking so much excess calories via this effervescent tablet.

Most apps and devices like Garmin show the energy burnt by a running, cycling or swimming activity in calories. Here is what my Garmin Connect app shows me for a recent run:

It shows that I burnt 601 calories after running 10K.

Now if I consume a minuscule effervescent tablet after my run, will I be consuming 13000 calories or almost 22 times the energy burnt from my 10K run? To burn of all these calories, will I have to do a 10K run 22 times or said in another way, run 220 km?

Is our body so efficient while exercising?

No! Most definitely not!

If it were, it would not generate so much heat (wasted energy!) during physical activity,

And we would not be sweating so much to aid in the dissipation of all that heat.

And the marathon world record could also have been set in hotter races like maybe the Mumbai Marathon.

And we could run round the world with nothing more than water and a tube of effervescent tablets 🙂

Then what gives?

The source of confusion lies in the fact that those well-meaning apps and devices mean kilo calories when they say calories.

Yes, its become a sort-of convention to show energy burnt in calories, when actually its kilo calories. Often the misleading labels also go the other way round. Many food nutritional labels show the energy in food in calories, when they actually mean kilo calories.

Yes, its confusing, but that’s how it is. Just remember that food energy always means kilo calories whether it says calories or kilo calories. And the same goes for the energy burnt metric shown by fitness apps and devices.

With this new clarity, what can we say about the energy in that piddly diddly effervescent tablet?

It contains 13 kcal. Or about the same energy I would have burnt in running about .2 km or 200m at that pace.

That’s not much. The athlete should not be afraid of such a teeny weeny effervescent tablet. Go ahead and consume it post run if you like it and if you believe it helps your hydration and electrolyte intake.

Happy Training!

-Coach Atul Godbole

P.S: Whats with the kJ that some nutritional labels mention? That’s kilo Joules, another unit of energy measurement. The conversion formula is simple: 1 kJ = 4.2 kCal (4.184 to be exact!). In other words the kJ is the bigger unit.


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