Final answer:
The blood pressure when the heart is contracting is the systolic pressure, which is the higher value in a blood pressure reading and indicates the pressure in the arteries during heartbeats.
Step-by-step explanation:
The blood pressure when the heart is contracting is known as the systolic pressure. This is the higher value recorded during a blood pressure measurement and reflects the pressure inside arteries resulting from the heart's ventricular contraction. Systolic pressure can be in the range of 100 to 200 mm Hg with a desirable systolic pressure being between 100 to 120 mm Hg. The diastolic pressure, which is the lower value of a blood pressure reading, represents the pressure during ventricular relaxation when the heart refills with blood. A sphygmomanometer, which is not the correct answer, is the device used to measure these pressures.