First let me preface this by telling you all that I am not a doctor. Everybody has some nagging aches and pains. Knowing when to deal with them is the big question. I have very bad knees from years of Army abuse. I figured that to avoid more surgeries I need to work on two things. Stretching and weights. Stretching along with hydration keeps your muscles in tip top shape. Once you have reached a good routine with stretching, introduce weights next. You don't really need to strive for the muscle freak look. Build strength and muscle mass by working up to a comfortable level. Never start at max. You will hurt yourself. Once you have stretched, started he weights, move on to running. Don't think of how fast and far you ran in high school. If you are like me, you are older and tired. Run 1/4 mile. Check your breathing and pace. If something hurts stop and triage. A pinch in your knee could just be the shock your under used joints yelling at you. It will go away! If you can't walk call a doctor. Don't be afraid to use ice, heat, and Tylenol until you get used to it. Just don't give up.