What is Cardiorespiratory Fitness?

Cardiorespiratory fitness refers to how well the body can move oxygen from blood to muscles during prolonged physical exercise. Absorption of oxygen and generation of adenosine triphosphate (ATP) by muscles is also referred to as cardiorespiratory fitness. ATP is used for cellular activity in the body when cellular energy levels are low. In a fitness setting, cardiorespiratory fitness is often broken down into transportation of oxygen and absorption and use of oxygen.

Transportation of oxygen starts during inhalation. Oxygen is taken into the lungs and absorbed by capillaries. Once oxygen passes through the heart, it is pushed out to various muscles and organs, where oxygen is absorbed before the blood returns to heart and eventually back to lungs for more oxygen. The first stage of cardiorespiratory fitness measures how effective this process is in the body.

When oxygen reaches muscles, the second stage of cardiorespiratory fitness begins. Muscles must work to absorb oxygen and generate ATP. More muscles in a given area typically mean more capillaries. Additional capillaries can improve this type of fitness. Once absorbed, mitochondria transform that oxygen to ATP. Mitochondria are small organelles responsible for various aspects of cell health and energy production.

Building cardiorespiratory fitness involves building more muscle tissue and increasing lung capacity through aerobic and anaerobic activity. Aerobic activity refers to exercise requiring frequent oxygen exchange, such as running, jogging, or swimming. Anaerobic activity does not require high levels of oxygen. These exercises can include weight training and stretching.

Aerobic and anaerobic activity work together to increase cardiorespiratory fitness. Aerobic activity may help to increase lung capacity and transportation of oxygen from lungs to blood. Anaerobic activity works to increase muscle mass for additional oxygen absorbing capillaries, and better effectiveness of oxygen absorption.

There are three common forms of cardiorespiratory exercise — simple, moderate, and uncontrolled. Simple exercises include walking, jogging, and elliptical training. Moderate exercises include swimming, in-line skating, and jumping rope. Uncontrollable exercises may be more fun, but heart rate and intensity is often dependent on individual situation and skill level. These exercises can include basketball, baseball, and volleyball.

Cardiorespiratory fitness typically responds to working out 20 to 60 minutes per session. It is important to maintain energy levels and attention to exercise during activity, to increase fitness levels and decrease chance of injury. Some beginners find it easier to break up exercise into two to three smaller sessions per day. For instance, working out three times a day for 10 minutes is the same as 30 minutes of exercise.

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Post 7

I try to keep a good balance of cardio exercise for my heart and lungs along with strength training for toning my muscles.

There are many days when I know I don't have an hour to work out. I try to get in at least 20-30 minutes of a good cardio workout on those days.

I think I need to get in at least 20 minutes to get my heart rate where it is supposed to be. Not only do I enjoy the health benefits of exercise, but can really feel it when those endorphins kick in.

Post 6

It seems like the guidelines for how long and how often you should exercise seem to change frequently. They all agree that some form of consistent exercise is good for you, so that is a good starting place anyway.

I have found if I don't keep up with my aerobic exercise, I can really tell a difference in my breathing when I go up and down stairs or climb up a hill or steep incline.

I have never had any kind of professional cardiorespiratory fitness test done, but know when I am out of shape.

Once I begin a regular and consistent aerobic exercise routine, it doesn't take long to feel the difference - even in doing everyday activities.

Post 5

@SailorJerry - Another way to get more exercise benefits is to do interval training. It lends itself well to either simple or moderate exercise. Basically, you just take it up for a little bit.

There are several different kinds of intervals you can do. I take a rowing class sometimes where we might "jog" for three minutes, then alternate between "sprints" and an easy "walking" type pace on a twenty second-forty second page. If you were walking, you would just walk faster, or you could turn up the resistance on the elliptical training or jog faster.

The intervals are supposed to really up your cardiovascular fitness. And they also help make exercise less monotonous!

Post 4

I've read that for average, healthy people, the best thing is to do sixty minutes of moderate activity every day, but then to sometimes take it up a notch. They say that when you are exercising aerobically, you should be able to talk but not to sing.

What I saw was that for twenty minutes, three times a week, it may be beneficial to work harder, to push yourself to the point where you cannot talk in complete sentences. (You should be able to get out a few words together, but not to carry on a conversation.) So if your usual cardiorespiratory fitness exercise is jogging, you might run hard for twenty minutes. Or if you usually walk, you might break into an easy jog (or alternate walking and jogging) or put an incline on the treadmill, if you use one.

Post 3

As a runner, cardiorespiratory fitness is really important to me. I haven't done a physical fitness test, exactly, but I have a heart rate monitor that I use a lot. It helps me judge my own aerobic fitness based on how hard a run feels at a certain heart rate, and how long I can run at higher rates.

Post 2

@hyrax53- I've heard about things like that for people asthma and other breathing problems too. I think it helps symptoms, even though it can't cure the problem. It's really important to monitor cardio exercise carefully though, especially if you aren't used to it. It's easy to get injured, or worse, just jumping into exercise.

Post 1

My dad has COPD. Since he got diagnosed, he's been going to "training" sessions where they constantly work on increasing and testing his cardiovascular fitness. He thinks it's worked really well so far- I guess if you have weak cardiorespiratory endurance, the best thing is to just keep trying to improve it.

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