Exercise corrects the blood circulation, and so cellular metabolism is at its optimum level. Hence the organs function at its best, more specifically
liver , heart kidneys etc.The proper circulation, prevents cholesterol plaque formation and hence prevents atherosclerosis. Secondly , proper excercise demands more calories , so food fat needs more bile acids to be emulsified, to get absorbed and produce energy. Usage of more bile means utilisation of cholesterol from blood..and stored fat from adipose is also removed with exercise..
So many reasons.