The cardiovascular system

Immediate effects when first exercising:

• Heart contracts more often – increased heart rate.
• Heart contracts more powerfully – increased stroke volume, which is the volume of blood pumped from heart with each beat.
• Blood diverted to muscles, eg it is diverted from the digestive system to the muscles.
• Blood temperature rises.
• Blood vessels near skin open to allow heat to be lost.

Effects of regular training:

• Heart muscle increases in size and strength.
• Cardiac output increases. Cardiac means relating to the heart so this is the amount of blood that the heart pumps out to the body.
• Lower resting heart rate, quicker recovery from exercise.
• Reduced risk of heart disease.
• Increased number of capillaries in muscles.
• Increased volume of blood and red blood cells