Dear Penguin

I have been running since Dec 09, have run a few 5K’s and now am embarking on some 10K’s. I would like to start training for a half marathon, the problem I have is that I’m recovering from insulin resistance and am very sensitive to sugar and carbs in general. At what point do I need to fuel while running and what can I use to fuel at that point.

If I use a energy bar I’m afraid it’ll raise my blood sugar/insulin too quickly.


It’s a great question. I’m not a doctor so please take everything I say as anecdotal.

In many ways all long-distance runners need to manage their blood sugar. One of the issues that we all need to address it how to stay fueled. You situation may be more complicated, but it’s not unique.

I was diagnosed with reactive hypoglycemia. If I eat sugar my body over reacts, releases way to much insulin, and my blood sugar drops. I have to be very, VERY careful about using the high carb, high sugar products.

The truth is that for years and years people ran marathons without taking in anything but water. It’s only recently that we’ve believed that we have to eat our way through a long distance race. So, don’t start with the assumption that you HAVE to eat something.

For me it came down to making sure that my every day nutrition was working. I monitored my blood sugar 4 or 5 times a day. I’d measure it before a run, and after. I experimented with some of the higher protein energy bars to see if any of them worked. Some did. Some didn’t.

Eventually I found that if my normal nutrition was right I could run everything up to a marathon using only water – or an occasional highly diluted sports drink.

So, become a mad scientist and find what works for you.

Waddle on,

john_jbr_150hJohn “the Penguin” Bingham, Competitor Magazine columnist
Author, The Courage to Start, No Need for Speed, Marathoning for Mortals and Running for Mortals.

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