Each year, nearly half of all runners in the U.S. wrestle with some type of pain or injury. The most commonly affected area, totaling 27 percent of running injuries is—you guessed it—the knee. If you have knee pain while running , your first instinct may be to zero in on the joint itself, but surprise! Strengthening muscles further up the kinetic chain is a better bet, and that’s where glute exercises can come into play to protect you from the discomfort. “The glute, in my mind, is one of the first places that I look when somebody’s telling me they’ve got knee problems,” says exercise physiologist Janet Hamilton, C.S.C.S., Georgia-based running coach with Running Strong . Why is knee pain a common symptom of weak glutes ? We break it down, plus explain exactly how to strengthen these muscles without aggravating the knee so you can keep running long and strong.…