It’s fine to have a banana or two before a big race, but if you are expecting that they will prevent painful muscle cramps you will probably be disappointed. Increasing the intake of foods that are high in electrolytes like potassium has not been shown to have much of an effect in warding off muscle cramps. While electrolytes such as potassium do play a key role in keeping water properly balanced inside and outside of your body’s cells, most researchers now believe that muscle cramps are caused by more than an imbalance of electrolyte levels. In fact, two studies of Ironman triathletes, done in 2005 and 2010, did not show any association with the electrolyte levels of the athletes and muscle cramping during exercising.
Most researchers now believe that muscle cramps are actually caused by overstimulation of the motor neurons in the nervous system that relay messages and control our muscles. There is some evidence that drinks that contain vinegar, such as pickle juice, can help prevent and relieve muscle cramping while exercising. This has nothing to do with electrolyte levels, it is because the vinegar triggers a reflex after ingestion that reduces the motor neuron activity that leads to cramping muscles. (In other words, vinegar sends a signal to the brain to tell the muscles to stop contracting and relax.) In fact, a number of studies have confirmed that pickle juice is more effective than sports drinks at treating muscle cramps, including this study at the Department of Health, Nutrition and Exercise Science at North Dakota State University. So you may be better off drinking a little pickle juice instead of a sports drink before or during your next athletic event.