I've been told that to reduce your LDL you need to modify your diet, quit smoking and do some exercise.

The first two, I understand. But, I don't understand how exercising can help reduce cholesterol.

In fact, it almost seems like exercising would make your risk of a heart attack greater. During exercise your arteries are expected to deliver more oxygen rich blood to the heart (so that you don't have a heart attack from lack of oxygen)... how can your already partially clogged arteries do this until your cholesterol level is lowered?

Thanks for any answers