How Many Calories Do I Really Need?


Is there a formula to calculate how much sports drink and energy gel I need on a ride? It's easy to keep swilling drinks and popping gels, but if I don't need all those calories for the ride, won't I just put on weight? -- Peter C.

Coach Fred Matheny Replies: 

That's a real good question, Peter, and the answer is -- it depends!

Caloric needs vary depending on body size, the ride's terrain, weather, intensity and duration, and factors such as how much you've eaten for your pre-ride meal and whether it's a one-day ride followed by a recovery day or you're in the middle of a tour, camp or stage race. So, any caloric recommendations by me or other coaches are necessarily approximations.

The same is true of hydration. Things like temperature and humidity, your hydration state going into the ride and your training during the previous days combine to make standard fluid replacement recommendations inexact.

In this and many other physiological areas, we're all experiments of one. Here are 3 key considerations:

1.    What is the minimum amount of food that allows you to last the distance without fading due to lack of fuel?

2.    How much food causes digestive discomfort or even weight gain? 

3.    How much sports drink allows you to avoid dehydration, overheating and cramping but not feel bloated and needing frequent pit stops?

When I started riding in the early 1970s, we didn't have energy bars or drinks (except Coke). Bottles were small and bikes had only one cage. I routinely did 3-hour rides on 20 ounces of water and a few fig bars.

Of course, I was younger, stronger (and dumber) then. But I think the human body can adapt to differing amounts of food and fluid, at least within reasonable limits. If it didn't, our ancestors would have died out 100,000 years ago.

I hope you understand why this answer seems wishy-washy. I think the best approach is to follow the dosage recommendations on the labels of the foods and drinks you're using. If you feel good, experiment with less to judge the effect. Then learn how the variety of factors I've mentioned can change your needs on a given ride.

Warning!  Never bonk. Reducing calories (intentionally or not) to the point where you become drained on a ride can set back your form a week or more. Always carry a bit more food than you're sure you'll need, just in case. Remember, though -- just because you have it doesn't mean you have to eat it.

Coach Fred Matheny has decades of experience as a competitive racer and cycling coach. He is the author of 13 RBR eBooks and eArticles.

[Coach John Hughes has written a number of information-packed eArticles on nutrition.]


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