Fueling for Marathon Swims: Why This Diabetic Guy Drinks Maple Syrup

I’ve had Type 1 diabetes for over 50 years now, and I’ve been training to do the 12.5 mile Swim Around Key West in June. It’s a challenge for anyone, only made harder if you’re trying to manage an autoimmune condition. In the summer of 2022, I completed the half-distance (10K, 6.2 mile) swim at Key West.

Just a week ago I shared my progress from a 6-mile training swim with a friend who wasn’t diabetic. He asked what I did for fuel. I told him I basically drank maple syrup, and the look of shock on his face was priceless.

Maple syrup…really? But what about your diabetes?

Yeah, about that.

I’m pretty up-front about the challenges of getting things right with diabetes and exercise. Exercise drops blood sugar, and if you’re not careful, it drops it too much. After a workout, you can end up with a severe and potentially fatal hypoglycemic episode, something called “Dead in Bed syndrome”, and that possibility scared me so much that I actively avoided exercise for 32 years. It literally took increasing visual impairment to force me to face that fear and take on the risks of being physically active. I blogged more about that in my recent article, The No Wake Zone, so I won’t belabor it here. But suffice it to say that when it comes to fueling for long swims, I don’t head out without a plan.

In the pool, I test my sugar hourly with a glucose meter. In open water, blood glucose measurements from the Dexcom glucose sensor I wear are sent to my Garmin sports watch. So that handles the glucose readings part of things. I don’t generally take extra insulin for swims, so apart from needing to get a baseline dose from my insulin pump, which I wear in a waterproof waist pack, that’s not really a worry.

But fueling is. Get it wrong and you’re having seizures in the water.

During marathon swim events, it can be difficult to fuel. You need to hydrate, get electrolytes, and eventually, take on protein. You’re not allowed to exit the water or swim up to the boat for a meal, so you have to eat while swimming. I know some real hotshots out there who can wolf down a peanut butter sandwich while treading water, but that’s not me. If there’s anything I don’t like about my fuel mix: too salty, too tart, too thick, too pasty–I spit it out. If it doesn’t go down easy on the first swallow, it’s useless.

Which brings me to the whole maple syrup thing.

I was shooting a commercial in Denver (how many times do you get to say that?!) with another truly outstanding fellow Type 1, Olympic athlete Kris Freeman, who turned me on to the idea of fueling with maple syrup. It’s actually a lower glycemic index than most commercial runner’s gels, and frankly, tastes better. It’s also got potassium, electrolytes and a balanced energy delivery curve that make it a perfect athletic fuel that doesn’t spike blood sugars or fail to absorb during physical activity. Following Kris’s tip, I tried Untapped Energy Gels Salted Cocoa flavor.

I really like it. It’s just a bonus that it’s actually good athletic fuel. I use the individual packets, which are about the same shape and size as a powdered lemonade packet. The top rips off quickly and they tuck easily under the legs of my jammers so they’re accessible if I’m having a low blood sugar in the water. And it’s measured quantities, so I know the effect it’s going to have.

For my regular fuel stops on long swims, I have my kayaker hand me a pre-measured water and syrup mixture, with added whey protein. He keeps that in 24-oz thumb-action pop-top Contigo Jackson plastic water bottles in a small cooler that holds enough for 6-8 hours.

The ring at the top attaches to a carabiner and 20 or so feet of floating polypropylene rope that make it easier to spot the bottle and not get tangled in the rope. My kayaker throws the maple syrup bottle to me in the water, and when I’m done, hauls it back to the kayak. I usually consume about 50g worth of Untapped every hour or so along with about 6 oz of water.  

The whole setup helps keep my sugar stable so I can feel safe to challenge myself without getting into trouble.

So yes, my mind-blown non-diabetic friend, not just maple syrup, but salted, chocolate-flavored maple syrup. In packets, and in floaty, wide-mouthed plastic bottles thrown from a kayak. Because even though I’m not an Olympian, I, too, like staying in control and leaving nothing to chance. 

Oh! And I almost forgot: I came in 2nd at the 10K swim. Not bad for some diabetic guy.