Low blood pressure 110/70. Concerned. I'm a runner and exercise regularly. History of heart disease in family. Also, third number: bph: 66?

110/70 is normal. This is a normal blood pressure for an athlete. You should only be concerned if you are lightheaded, dizzy, fatigued, or short of breath. The normal response of blood pressure during exercise is for the top number to increase and the bottom number to decrease. It is normal for athletes to have lower blood pressures and heart rates due to the heart's adaptive response to exercise.