ASK JANICE The heart and the circulatory system (veins and arteries and a few other things), in our body is called the cardiovascular system. Everyone has one, even the Tin Man. This makes a network that delivers blood to the body’s tissues. With each heartbeat, blood is sent throughout our bodies, carrying oxygen and nutrients to all of our cells. It is incredible to think that every day, approximately 10 pints of blood in your body travels through the system of about 60,000 miles of blood vessels that branch and cross, linking the cells of our organs and muscles. The heart is the key organ in the circulatory system. As a hollow, muscular pump, its main function is to propel blood throughout the body. It usually beats from 60 to 100 times per minute, but can go much faster when it needs to. It beats about 100,000 times a day, more than 30 million times per year, and about 2.5 billion times in a 70-year lifetime.
The heart gets messages from the body that tells it when to pump more or less blood depending on a person's needs. When we're sleeping, it pumps just enough to provide for the lower amounts of oxygen needed by our bodies at rest. When we're exercising or frightened, the heart pumps faster to get more oxygen to our bodies.
Here comes the fun part – Your heart is a muscle as well as an organ. Fortunately it is an involuntary muscle so we don’t have to tell it to contract and relax. But like any other muscle, in order for it to be healthy it needs exercise. We think of cardiovascular exercise in two ways aerobic and anaerobic.
The literal meaning of aerobics is oxygen. Hence, aerobic exercise can be defined as the one, which involves the use of oxygen to produce energy, whereas anaerobic exercise makes the body to produce energy without using oxygen. Anaerobic exercises are high intensity workouts that are performed for a short time. On the contrary, aerobic exercises generally simple exercises and are performed for a longer time, at moderate intensity. A simple example: A five mile walk is aerobic whereas sprinting for a bus or running away from a tsunami is anaerobic. Both types of exercise are important because your body should be efficient in both.
The benefits of aerobic exercise are myriad, (like you haven’t heard this before):
ü Systemic changes such as reduced cholesterol and blood pressure
ü Improved muscular endurance
ü Reduced body fat,
ü Increased metabolism
ü Improves the strength of your bones, ligaments and tendons,
ü Allows your body to use fats and sugars more efficiently, burns lots of calories
ü Reduces your risk of heart disease, vascular disease and diabetes
ü Can help those trying to quit smoking by relieving cravings and improving lung function.
ü Reduces the onset and symptoms of aging and illness.
ü Aerobic activities strengthen the heart and lungs, making them more efficient and durable, improving quality and quantity of life.
ü Reduces stress and combats depression as it raises self-esteem and physical awareness.
ü Exercise not only extends your life, but also gives you more energy to live it to the fullest.
Given this incredible list of benefits it’s a wonder that more folks don’t exercise. Oh well just another one of those mysteries.
Aerobic exercise - how do you do it right? Before we get into anything fancy, there is a good rule of thumb to know when you are doing aerobic (cardio) exercise: you should be able to talk. If you are too winded you are working too hard a need to bring your heart rate down and get control of your breathing. If you do not have a heart rate monitor which makes life easy, takes all the guessing and frustration out of knowing where your heart rate is at any moment (I never leave home without mine), then you’re are going to have to depend on listening to your breathing which is not a bad thing. Listening to your breathing while jogging is hypnotic and meditative and one of the wonderful rewards of aerobic training. You will also want to take your pulse with your fingers.
The aerobic zone is your heart rate target zone based by the percentage of maximum heart rate. It’s not fun to do a max heart rate test and not recommended for beginners. So we have to make a good guess as to what that number is. You maximize the benefits of cardiovascular activity when you exercise in the zone of your target heart rate (THR). In general terms, your THR is 60-80% of your maximum heart rate. The Karvonen Method of calculating THR is one of the most effective methods to determine target heart rate because it takes into account resting heart rate. Here's how to find your THR.
- Find your resting heart rate as soon as you wake up. You can do this by counting your pulse for one minute while still in bed. You may average your heart rate over three mornings to obtain your average resting heart rate (RHR). Add the three readings together, and divide that number by three to get the RHR. For example, (62 + 65 + 63) / 3= 63.
- Find your maximum heart rate and heart rate reserve. Subtract your age from 220. This is your maximum heart rate (HRmax). For example, the HRmax for a 40-year-old would be 220 - 40 = 180.
Subtract your RHR from your HRmax. This is your heart rate reserve (HRmaxRESERVE). For example, HRmaxRESERVE = 180 - 63 = 117
- Calculate the lower limit of your THR. Figure 60% of the HRmaxRESERVE (multiply by 0.6) and add your RHR to the answer. For example, (117 * 0.6) + 63 = 133.
- Calculate the upper limit of your THR. Figure 80% of the HRmaxRESERVE (multiply by 0.8) and add your RHR to the answer. For example, (117 * 0.8) + 63 = 157.
- Combine the values obtained in steps 3 and 4 and divide by the number 2. For example, (133 + 157) / 2 = 145 (You can get the same result by simply multiplying HRmaxRESERVE by 0.7 and adding to it RHR).
Now you know the rest of the story, go ahead and try it for yourself, you will be glad you did and that is a promise!