How Your Body Works: Cardiovascular System

Let's learn a bit about how the normal heart and blood vessels work. This basic knowledge will help you to better understand cardiovascular diseases later on.

The cardiovascular or circulatory system is made up of two components: the heart and the blood vessels. The heart is a muscular organ that pumps blood, while the blood vessels carry the blood to circulate all areas of your body.

The Heart

Your heart is made up of many parts working together to pump blood. An electrical system controls the heart and uses electrical signals to make the heart muscles contract. Like any other organ, the heart also requires oxygen and nutrients from the blood in order to function properly. Blood supply to the heart is provided by coronary arteries. 

If the coronary arteries get clogged up, such as what happened in coronary artery diseases, your heart muscles will be damaged and you'll end up with a heart attack or even a heart failure. If the electrical systems that control your heart are not working properly, your heart beat will become irregular, a condition called arrhythmia. It can either beat too fast (tachycardia), too slow (bradycardia), or even stop entirely (asystole).

Anatomy of the heart

The heart is divided into four chamber: the right atrium, right ventricle, left atrium, and left ventricle. The ventricles are more muscular than the atria because they do most of the pumping work. The left sided chamber wall are normally thicker than the right because they handle the systemic circulation while the right sided chambers handle the pulmonary circulation. 

Each chamber has a valve at its exit that prevents blood from flowing backwards. The tricuspid valve is at the exit of the right atrium, the pulmonary valve at the exit of the right ventricle, the mitral valve at the exit of the left atrium and the aortic valve at the exit of the left ventricle. 

Blood Vessels

There are three major types of blood vessels in our body: 

• The arteries are blood vessels that carry the blood away from the heart.
• The capillaries are small vessels which enable the actual exchange of water and chemicals between the blood and the tissue 
• The veins which carry blood from the capillaries back toward the heart.

The blood picks up oxygen in the lungs then flows to the pulmonary veins, to the left atrium, through the mitral valve, to the left ventricle, through the aortic valve, to the aorta and finally to the whole body. 

After the oxygen is picked up by our organs, blood from the whole body flows to the superior and inferior vena cava then to the right atrium, through the tricuspid valve, to the right ventricle, through the pulmonic valve, to the pulmonary artery, and finally back to the lungs.

When your heart pumps blood through your arteries, it creates a pulse that you can feel on the arteries close to the skin's surface. For example, you can feel the pulse on the artery inside of your wrist, below your thumb. The normal resting pulse for an adult is 60 to 100 beats per minute.

---

Other articles on how your body works:

• The human respiratory system consists of a complex set of organs and tissues designed to capture oxygen from the environment and transport the it into the lungs. Read more about how your respiratory system works
• Everyone experience pain at some point of their life. Pain is the most common reason for physician consultation in the United States. Read more about physiology and psychology of pain
• Coughing is a protective reflex to clear the lungs and airways from foreign material. Rapid expulsion of air from the lungs pushes out the offending irritants like microbes, fluids, or mucus.Read more about the cough reflex
  

A Small List of Easy Exercises

Continuing from my last post about easy and enjoyable exercise, here are some examples of the easy exercises that will keep you healthy on the long run. Or if you're looking forward to weight loss, these are the the most healthy ways to do it. So, get up and leave your cozy couches behind to try these out:

1. House-cleaning

Why is it on top of the list? Because other than burning the calories, you'll have your home neat and tidy in no time. Mop the floor, vacuum the dust, move that stack of useless junk elsewhere. You can lose over 200 calories per hour if you put your back on it. 

Don't underestimate house-cleaning. Lose up to 200 calories per hour just by mopping the floor!

2. Aerobics

This type of exercise primarily targets the hip, bum and legs which most women want to tone up. It's also good for your cardiovascular health. Make sure you do it regularly. Just fifteen minutes of aerobics will take 200 calories off you.

3. Walking

This one is probably the easiest one to do and you may not realized that you're actually burning carbs while doing it. Make a few rounds in your house or go out to get some fresh air in the park. Take the stairs instead of the elevator. If you take the bus, get down a few stops earlier and walk rest of the distance. To get the most out of walking, try to walk faster than a stroll. However, even walking as slow as 2.5 Mph for an hour will burn off 200 calories.

4. Swimming

Another fun way to burn the calories. Swimming makes good work of most muscle groups in your body. If you increase the pace, you’ll get a good aerobic exercise with less strains on your joints. It's especially helpful if you have back or knee pain, but want to find ways to stay physically active. Going back and forth the length of the pool for half an hour burn around 400 calories.

---

Other articles in exercise:

• In the year 2008 physical inactivity was responsible for the deaths of 5.3 million. These deaths could be avoided if only people would take 150 minutes or more of moderate exercise weekly. Read more about physical inactivity and the problems it brings
• Ever find yourself in need of a push to get you up in the morning and do some physical exercise? Read more about how to make exercise easy and enjoyable
• A lot of seniors feel discouraged to do physical exercises because concerns about injury or falls. Sometimes a health condition such as heart disease and osteoarthritis can also prevent them from staying active. Read more about exercise for older adults and the elderly