Someone cramps up on the pitch and the advice is always the same: eat a banana, you're low on potassium. In this episode, I put that advice to the test, along with two more banana myths that fill fitness feeds.

Myth 1: bananas fix cramps. A small crossover trial found that eating bananas after exercise raised blood potassium only marginally, within normal values, and not fast enough to stop a cramp. Exercise cramps look far more neuromuscular than nutritional.

Myth 2: "it's not about the carbs." When 14 trained cyclists rode 75 km on either bananas or a 6% carbohydrate drink, blood glucose and performance didn't differ. The banana works because it's excellent fuel. (The study was funded by Dole — worth knowing.)

Myth 3: banana tryptophan makes exercise feel easier. A banana has about 10 mg of tryptophan, a tiny fraction of the d ...