Weak/tight glutes are the cause of countless problems
A good place to start is with a simple diagnostic test. Stand on one leg and check that the knee is over the middle toe of the foot. Then do some knee bends and have a partner observe. If the knee is moving in when you bend this is sign of weak glutes and probably and over active TFL (the small muscle in the hip which has the IT Band as its tendon.
Lie on you side with feet, knees and hips on top of each other. Put a hand on your backside to feel the muscle then squeeze gently o lift the top leg (keeping the feet together). Hold at the top and lower back down while keeping the muscle squeezed (often the most difficult part)
Once the basic lunge is mastered you can move to a more dynamic lunge in a forward direction. Variations including a backward lunge and lunge with twist and explained and demonstrated very well by Jay Johnson on You tube.
Stretching tight qu
Lie on the side with the bottom leg at 90 degrees to lock the pelvis. Grasp the top leg at the ankle and bring the foot towards the buttock until you feel the stretch.
To stretch the glutes lie on you ba