“What do you eat?” is a question that I get asked a lot. After years of fine tuning my feeds, I finally have an answer that doesn’t require explaining the recipe for a homemade concoction - - ‘I eat peanut butter and jelly’. Not really but its pretty close.
Every open water marathon swimmer has his or her own journey to find the right fuel for their metabolism and taste. Mine started with the standard approach, Gu and a sports drink that I tried during training swims but I quickly learned that this really didn’t work well for me. I explored what other endurance athletes ate and came to the conclusion that I needed:
- A lot of calories from protein and fat
- some % of carbs
- Food that was closer to what I eat all the time so I don’t stress out my GI system (for a cold water swimmer stomach issues are huge since we need to keep in calories and throwing up in the water is not good –you can aspirate water and then you have a whole new set of issues).
Based upon my weight, the need to generate body heat and the pace that I swim (~ 72 strokes per minute), I estimate that I burn about 1,000 calories an hour in cold water. Its well established that the average amount of calories that a person can process is between 300 – 350 per hour. So, its not possible to take in all the calories that I’m burning. After practicing during long training swims, I know that I can process 350 calories and sustain my pace and body heat.
The final variable for feeding during marathon swims is that a feed has to be quick. Wasting time fiddling with a package means you lose body heat and you could go backwards if you are in the middle of a current.
The food, frequency and feeding method that works for me is:
1. eat every 30 minutes
2. take in 8 oz of Perpetuem at the bottom of the hour
3. eat 1 packet of Justin’s Nut Butter and 1 sachet of blueberry toddler food + 8 oz of Perpetuem
4. chocolate treat every once in a while spontaneously given by my crew
I might even add a Coke just for the caffeine and sugar boost when I'm a couple of miles from the end for good measure :-)