You've probably heard several of them numerous times—"be sure to stretch before you run" and "always finish your runs with a cool down"—but is there any real truth to them?
We asked exercise science expert Michele Olson, PhD, FACSM, CSCS, professor of exercise science at Auburn University Montgomery, and creator of the Perfect Legs, Glutes & Abs DVD to help us sort out the facts from fiction of these popular running misconceptions.
Myth: You Should Always Stretch Before You Run
The Truth: "Static stretching is not the optimal way to warm-up before you run," Olson says. Believe it or not, you could actually strain your muscles with static stretching, and it might even slow you down. Instead, focus on getting oxygen to your muscles and warm them up—literally, Olson recommends. "Start out by walking and trotting: swing your arms; shrug your shoulders and slowly elevate your heart rate for about 10 minutes before you pick up your pace."
That doesn’t mean you should skip stretching completely, Olson says. Just make sure to do it after your run, when your muscles are very warm and full of oxygen and nutrients; and then engage in static stretching, focusing on your leg, hip, and low-back muscles.
Myth: Muscle Cramps are Always Caused by Too Little Potassium
The Truth: Muscle spasms can certainly put a cramp in your running style, but that doesn’t mean you need to load up on potassium to prevent them. "Cramps are primarily caused by either being low on glucose (the form of sugar your muscles thrive on for energy) or low water and sodium levels," Olson says. When you are working out very hard (like lifting weights or with intense intervals), you use up glucose faster than what can be delivered to the muscles, and this causes that muscle-burning lactic acid to form. The best way to get rid of cramps caused by low glucose levels is to take a 60-90 second break to help rid your body of lactic acid and allow glucose to travel to the muscles, Olson says.
To prevent cramps caused by excessive sweating during steamy outdoor runs, be sure to stay well hydrated and nourished, Olson says. “When you sweat, sodium is also excreted, and water and sodium go hand-in-hand. Losing significant levels of potassium is actually quite hard to do. Potassium lives inside our cells and is not excreted as readily as sodium. Sodium, like water, resides outside the cells in your body.”