And no one can say for sure why women appear to do better at longer distances. That's what I want to know. A handful of scientists have taken a stab at those sorts of studies. Here's the existing evidence. You decide whether it has legs.
Women can use body fat as fuel.
Her thinking was women could draw on their more ample fat reserves, using them for fuel in long races. It was an intriguing theory, but one that was short on evidence. That is, until recently, when Mark Tarnopolsky, M.D., Ph.D., assistant professor of medicine at McMaster Medical Center in Hamilton, Ontario, took up the torch. If you can increase the amount of fat your muscles use for fuel, you can spare glycogen. And that's important, because when you run out of glycogen, you have to slow down.