Patrick Sayers 12/5/12 Period 9 My hypothesis is correct. My hypothesis is when you exercise; your pulse rate will go up. Exercise causes your heart to work harder to deliver more blood to energy-hungry muscles, which increases your heart rate. When you feel someone's pulse or your own, you are feeling the pressure pulses created by the beating of the heart. The increased pulse rate increases your heart rate. Blood flows more vigorously through the body which leads to an increase in blood pressure. There is no pattern is the histogram because the pulse rate is random.