Will Eating Candy Help You Run a Marathon?

Long distance runners tend to "carbo-load".

Posted Mar 23, 2011

The Boston marathon is about a month away, and the streets are filled with runners getting in their miles.  I have a neighbor whom I saw on the sidewalk preparing for his weekly 20 mile training run. He was squeezing the last of an energy gel called GU into his mouth. GU is sticky, gel-like substance made out of glucose and packaged in containers similar in size to ketchup and mayonnaise containers found in fast-food restaurants. 

I asked him if he eats more GU later on in the training run, and he told me he consumes a second packet around mile 15.

"My muscles are really tired by then and they need that energy boost," he replied. "This year I am carrying them when I run the Boston Marathon to see if it improves my time."

Energy gels have been around for a few decades, although people who do not regularly browse sports apparel stores might be unaware of them. They are usually found near the checkout counter; several companies make this concentrated form of sugar to be used for any type of endurance sport. They contain just glucose and some nice flavorings like chocolate, vanilla and orange cream.

The science behind them is compelling. Glucose is the basic unit of carbohydrate. All carbohydrate is digested to glucose, which then participates in a complex series of biochemical steps to make a form of energy usable by the body. Some of the glucose that is not used immediately for energy is stored in the muscle in the form of a starch-like substance called glycogen. When needed for energy, the glycogen emerges from the muscle and is changed back to glucose. Long-distance runners tend to "carbo-load" before a race to store as much glycogen as possible in their muscles and, like my neighbor, also eat their energy as a sports gel.

One problem with the gels is that the package may be difficult to open, especially in the middle of a run. If you have ever tried to open a fast-food restaurant ketchup packet when your hands are sweaty you will understand the difficulty. Teeth help but using the mouth to open the packets may affect the breathing rhythm and in a worse case scenario, the packet could be swallowed.

An obvious and seasonal solution to getting enough energy during the Boston Marathon, which always takes place in April, is to eat a few PEEPS. These garishly colorful candies are prominently displayed in every chain drug store. PEEPS are marshmallows that have had a total body makeover. The blobby pasty white marshmallows are, depending on the season, transformed into spiffy-looking baby animals, Santa Claus, ghosts or pumpkins.  They are made out of sugar, gelatin and, presumably, lots of food color.

 PEEPS will never make it into any desirable food group, but the endurance athlete should consider them as a ready and convenient source of energy. Like the energy gels, they contain no fat or fiber. Thus they are digested very quickly and send glucose into the bloodstream for the struggling runner or long-distance biker or cross-country skier. And they have one main advantage over the energy gels. There is no packet to open, no gel to squirt on the tongue and the runner doesn't need water to swallow the gooey stuff.  A baby chicken or rabbit can be swallowed with a few bites. The cost of a barnyard full of PEEPS is about the same as one packet of GU.

Despite the reasonableness of my argument for eating these confections during training or a race, I suspect no one will do so. Green marshmallow bunnies don't have the 'sports authority' of an energy gel despite the fact that the body probably can't tell the difference once they are digested.  But the real problem is the difference in perception of the nutritional value of GU versus PEEPS.  Both deliver sugar to the body quickly. Both will provide needed energy for muscles and other cells. But PEEPS are perceived as having no nutritional value whereas GU and other energy gels are considered valuable for enhanced athletic performance. 

There seems to be a double standard when it comes to sugar as the use of GU illustrates. Sugar has become the 21st century nutritional terrorist, if one believes many articles in the media and on the Internet. It has been linked to all the health ills characterizing our society. Yet the sports community accepts the concept of ingesting sugar so the muscles work faster, longer, and better during training and competitive events. These energy gels were developed after a great deal of laboratory research on muscle work and athletic performance; they didn't just appear because someone wanted to use up left- over frosting. And despite all the hype about the advantages of eating only a high- protein, high-fat diet, I doubt that any long distance runner, biker or triathlon participant is going to chew on a chunk of lard or pork rind in the middle of the race when energy is needed.

I doubt if next year we will be seeing PEEPS in the form of a marshmallow marathoner nor do I expect runners to be chomping off the head of bunnies as they stagger up Heartbreak Hill. But if you are watching the race and you see someone squeezing a sugary substance over his tongue and trying to swallow it with a parched mouth, you might just hand the runner a chick and say, "Try this."