Cardiovascular Fitness What is cardiovascular fitness? Cardiovascular fitness is the body’s ability to provide oxygen continuously to muscles as work is performed over an extended period of time. There are two components of cardiovascular fitness: circulatory and respiratory systems The circulatory system consists of the heart, blood, and the blood vessels. The respiratory system consists of the lungs and the air passages. Together these two systems work to provide muscles with the needed oxygen to perform daily activities. How do we achieve and maintain cardiovascular fitness? Exercise is an important factor in achieving and maintaining cardiovascular fitness. To increase cardiovascular fitness you must engage in exercises that involve movements of the large muscles of the body. You must also be able to maintain these exercises continuously for at least 20 to 30 minutes. These exercises are called aerobic because the working muscles continue to receive as much oxygen as they need. Brisk walking, cycling, jogging, and swimming are all examples of aerobic exercises. How much exercise do I need to maintain good cardiovascular fitness? The purpose of a cardiovascular fitness program is to increase the body’s ability to use oxygen. One way to increase the oxygen supply to all muscles is to develop the muscle that serves as the pump, the heart. Since the heart is a muscle, it responds to training like other muscles. To develop the heart muscle, you must push it beyond its normal range and make it pump more blood with each heartbeat. This additional overload can be placed on the heart by an increase in the (FIT) frequency, intensity, or time(duration) of the exercise program. Frequency: Aerobic activities must be performed at least 3 times per week to reach and maintain an adequate level of cardiovascular fitness. To increase the frequency you simply exercise 4 to 5 days a week instead of 3. Intensity: You cannot observe your heart becoming stronger as you can the biceps. Therefore, you must rely upon the pulse/heart rate. The pulse rate is the external sign of the heart’s condition since it corresponds exactly to the beat of the heart. The intensity of the exercise may be determined by the response of the pulse rate. The recommended intensity of your training should be such that you increase your heart rate to 60 to 90 percent of your maximum heart rate (MHR). The 60 to 90 percent of your heart rate is termed target heart rate (THR). In other words when you work out, you should maintain your heart beat within the limits of your target heart rate (THR). Following is an example of the THR for an 18 year old. The MHR is 220 – your age. (MHR for an 18 year old: 220-18=202/the MHR is 202)To compute your (THR) simply multiply your MHR by 60% (lower limit of THR) and again by 90% (upper limit of your THR). 202x.60=121 202x.90=182 The THR for an 18 year old is between 121 and 182. Once the THR is known, you will be able to check the intensity of your exercise by stopping briefly from time to time to check your pulse rate. To measure your pulse rate place your index and middle finger on your neck midway between your ear lobe and adams apple (carotid pulse) or the inside of your wrist (radial pulse) and begin counting from zero for 6 seconds, then add a zero to the end. Time: To achieve all the values of cardiovascular training, you must maintain the THR for a minimum of 20-30 minutes. To increase the overload, you may increase the time to 35 or 40 minutes. How do I know my cardiovascular fitness program is working? Since the heart is a muscle, it becomes stronger when exercised. By keeping a record of your resting heart rate (RHR) you can measure the progress gained in your cardiovascular fitness. An active person has a lower RHR than an inactive person. After a few months of cardiovascular training you should note a decrease in the RHR. To measure you RHR, take your pulse in the morning just after waking and before getting out of bed. Your pulse should be taken while sitting or lying down. A normal RHR is between 50100 beats per minute (bpm).