LESSON 6.1 S.JETT, NBCT MONTEVALLO MIDDLE FITNESS FOR LIFE – CORBIN & LINDSEY ACTIVITY AND CARDIOVASCULAR FITNESS

Activity and Cardio When you do regular physical activity, you improve your cardiovascular fitness – fitness of the heart, lungs, blood and vessels. Of the 11 parts of fitness, cardio is the most important because those that have it receive many health and wellness benefits including a chance for a longer life.

Benefits Looking good is important to most people, and you are most likely one of them. Doing regular physical activity can help you look better by controlling your weight, building muscle, and developing good posture. In addition, regular physical activity produces changes in the body organs such as making your heart muscle stronger and your blood vessels healthier. These changes result in better cardiovascular fitness and wellness, as well as a reduction in risk of hypokinetic disease.

Regular PA Regular PA benefits two vital body systems. Your cardiovascular system includes your heart, vessels, and your blood. Your respiratory system includes your lungs and the air passages that bring air, including oxygen, from outside the body to the lungs. In your lungs oxygen enters your blood while carbon dioxide is eliminated. These systems both work together to bring your body the materials it needs and also functions to get rid of waste. Exercise helps your body function more efficiently. What does efficiently mean?

Heart Because your heart is a muscle, it benefits from exercise and activities such as jogging, swimming, hiking, etc. Your heart acts as a pump to supply blood to the body. When you do vigorous activity, your cells need more oxygen and produce more waste products. Your heart must pump more blood to meet the demand for intake and removal. If your heart isn’t able to pump enough blood, the ability of your muscles to contract will be reduced and they will become fatigued more quickly.

Heart cont. Obviously, your hearts’ ability to pump blood is very important. Your heart has 2 ways to get more blood to the muscle – 1) by beating faster or 2) sending more blood with each pump. Do you recall what a good resting heart rate would be? If someone is not active, he/she may have a higher resting heart rate and when he/she exercises the heart will have to work way too hard.

Arteries Your arteries carry blood away from the heart to other parts of the body. Blood is forced through your arteries by the beat of your heart. A strong heart and healthy lungs are not very helpful if your arteries are not clean and open. You know that fatty deposits on the lining of the vessels lead to atherosclerosis and that can totally block the blood flow in an artery. The hardened deposits can also form blood clots that will completely restrict the flow of blood and cause a heart attack.

Blood Although your body needs a certain amount of fat, excessive amounts trigger formation of the fatty deposits along the artery walls. Cholesterol, a fatty substance found in meats, dairy products, and egg yolks, can be dangerous because high levels can build in your body without you noticing it. Cholesterol is carried in the blood by particles called lipoproteins. One kind, low density lipoprotein (LDL), is often referred to as “bad cholesterol.” The high density lipoprotein (HDL) is referred to as “good cholesterol.” HDL’s carry the bad cholesterol out of the blood and to the liver.

Regular PA Regular PA helps improve your cardio by reducing LDL and increasing HDL. Exercise can also help prevent blood clots from happening by reducing the amount of fibrin in the blood. Regular PA also has other benefits. Scientists have found that people who exercise regularly develop more branching in the arteries. After astronaut Ed White died in a fire in 1967 while training for a mission, an autopsy found that one artery was completely blocked. They believe that his high level of physical activity helped prevent him from having a heart attack.

Veins Your veins carry blood that is filled with waste products. One way valves in your veins keep the blood from flowing backward is by squeezing the veins to pump the blood. Regular exercise causes veins to squeeze more efficiently. A lack of PA can cause the valves, especially in the legs to stop working efficiently and proper circulation will be reduced.

Nerves Your heart muscle is not like your arm and leg muscles. When your arm and leg muscles contract, nerves in the muscle are responding to a message send by the conscious part of your brain. In contrast, your heart is not controlled voluntarily; it beats regularly without you telling it to do so. Regular exercise can influence your nervous system to slow down your heart rate. As a result, your heart works more efficiently because each heart beat supplies more blood and oxygen to the body.

Muscle Cells For you to be able to do physical activity for a long time without getting tired, your muscle cells must function efficiently and effectively. Regular PA helps cells use oxygen and get rid of waste materials effectively. PA also helps the muscle cells use blood sugar, with the aid of the hormone insulin, to produce energy. This is important to good cardiovascular health.

Benefits of PA on the Cardiovascular System HEART – Muscle gets stronger Pumps more blood with each beat Beats slower Gets more rest Works more efficiently LUNGS – Breathe slower and deeper during activity Work more efficiently Deliver more oxygen to the blood

More Benefits ARTERIES Less risk of atherosclerosis Lower blood pressure Less risk of a blood clot leading to heart attack Development of extra vessels Bigger arteries and more blood flow BLOOD Less bad cholesterol (LDL) More good cholesterol (HDL) Less substances that cause clots

More Benefits VEINS Healthy valves CELLS Use oxygen efficiently Get rid of more wastes Use blood sugars and insulin more effectively to produce energy

Cardiovascular Assessment How good is your fitness level? Special tests can assess your fitness. The Maximal Oxygen Uptake test is considered the best test of cardiovascular fitness. It is don in a laboratory using special equipment, including a gas meter and treadmill or stationary bike. Another type of lab test is the graded exercise test, sometimes call the stress test. This test requires the same equipment and a special heart rate monitor. These tests are often expensive because they require specialized equipment and experts to administer and interpret the results.

Self - Assessment There are several inexpensive ways that you can self- assess. Do you know of any of those assessments?

Interpreting Results It is always wise to do more than one assessment and even more than one type of assessment. Each assessment has its own strengths and weaknesses. The PACER and the One mile run are dependent on one’s motivation. If you don’t try very hard, then you will not score very well. The walking test is good but doesn’t require a high level of fitness. The step test will also give varying results depending on the previous activities. These tests can also be influenced by emotional factors.

How much is enough? To get good benefits, you should achieve ratings in the healthy heart zone. It is important to know that there are benefits associated with moving out of the low fitness zone. If you aspire to be an athlete, you will want to score in the high fitness zone.

Review 1. What are some benefits of PA on the cardio system? 2. What are some methods of assessment? 3. How much is enough?