i am 45 yrs old. i workout a lot but still have a big left hamstring problem. i can stretch the right leg to about a 100 degree angle [lying on my back, pulling my leg towards my chest]. my left leg i can only stretch to about a 45 to 60 degree angle. so basically it is real tight. i also get a lot pain when i kayak. is there something i can try to loosen it up.