Lisa’s Cardio

Cardiovascular training is an essential part of any exercise program.  The choice to ignore it is an ignorant one that I have been largely guilty of.  In fact, after my high school sports were over, I largely ignored cardiovascular training because I simply don’t enjoy it.  Then, I met Lisa and it’s her favorite thing since sliced bread, so I did cardio with her.  Now I do it because I want to keep my heart and arteries healthy.

As you can tell, I’m not much of a cardio guy.  Because of that, I asked Lisa to guest-author this part.

Cardiovascular Training

Put simply, cardiovascular training is anything that trains your heart and lungs to perform optimally.  So, the result of it is a lower heart rate, lower blood pressure, and better cholesterol levels.  Also, it seems to work well in decreasing insulin resistance and therefore decreasing your risk of diabetes.

So, how does somebody who has never focused on cardiovascular training start out?  Well, after they get a doctor’s notice if they have any questionable health problems, they start out very slowly.  The start of any cardiovascular program should be a warm up, and the end of any cardiovascular workout should be a cool down.  A warm up is important to gear the body up for the amount of work it’s going to be doing.  You must get your heart pumping gradually and your muscles warm before you jump into any activity.

Then, at the end of your workout, you should have a cool down.  This is to prevent blood pooling.  Blood pooling happens when you are doing intense exercise and you have a lot of blood pumping through your veins.  Veins cannot always move all of the blood themselves so they get help from the surrounding muscles.  Veins are also one-way valves.  So, at the end of an intense workout, you have a lot of blood pumping through your veins and then when you stop abruptly, the veins don’t have the help from the muscles anymore and the blood begins to pool.  When blood begins to pool, there is not as much blood going to the heart because it is stuck and there is potential for a heart attack.

That said, at the beginning, the point is to walk, bike, elliptical (or anything else that involves rhythmic movement of a bunch of muscles) at a pace where you’re not very out of breath.  After the warm-up, a good level to be at is a level where you can’t speak full paragraphs at a time, but also where you’re able to speak one or two sentences before having to gasp for breath.  It is smarter to start out conservatively and have to increase the intensity rather than starting out too high and risk injury, over-training, or lack of motivation.

And that’s how you start out.  You walk at that level of intensity for twenty minutes until that’s too easy.  Then, you move up to twenty-five minutes until that’s too easy.  Then, you keep on moving up by five minute increments until you’re at an hour.  A steady increase of 5-10 minutes every 1-2 weeks is best for the first 4-6 weeks of exercise.  Now, you’re ready to increase the intensity to something harder for a shorter duration.  As a general rule, you should only increase frequency, intensity, or duration about 10% per week.

The key here is that when dealing with cardiovascular training, you should always increase how long you do it before you increase how difficult it is.  For the average person, it is optimal to aerobically train 30-90 minutes, 3-5 times a week.  This should be done at 70-85% of your maximal attainable heart rate (MAHR), which is considered a moderate rate of activity.  Vigorous activity is anything above 85% of your MAHR.  ACSM guidelines state that in order to achieve and maintain health/fitness benefits, moderate intensity exercise should be done at least 5 days a week, or vigorous intensity 3 days a week, or a combination of vigorous and moderate intensity activity 3-5 days a week.

If you are just starting a program and haven’t trained ever or in a long time, then an appropriate range might be more like 55-65% of your MAHR, which is a low intensity activity.  To find your MAHR, you must take your age and subtract it from 220.  For example, I am 23, so I would subtract 23 from 220 to get that my MAHR is 197 beats per minute.  Since I am training, I will work in the 70-85% MAHR range and will calculate my lowest heart rate and and my highest heart rate that I should be training at.  To find this I take 197 x .70 which equals 137.9, which I will round to 138.  Then to get the top of my range I will take 197 x .85 which equals 167.45 and I will round that to 167.  Now I know to train at an intensity where my heart rate is between 138 and 167 beats per minute.

Next, I want to explain metabolic equivalents (METs).  A MET is a multiple of how hard your body is working compared to its resting state.  So if I’m working at a 5 MET level, then my body is working 5 times harder than it was at complete rest.  I am burning 5 times as many calories and taking in 5 times as much oxygen.  A good goal would be to eventually work up to 8-10 METs for a period of time.  This is a good measure of how hard you are working when you are working on a machine that measures your intensity in METs.

There is another commonly asked question about cardio machines that I would like to clear up as well.  On most cardio machines there is a chart that shows what heart rate range you should be working in to either be in a cardio zone or a fat burning zone.  You should pay no attention to this chart.  The thing you should focus on the most when trying to lose weight is how many total calories you burn.  The fat burning zone has you working at a lower intensity and so for the same amount of time you could have been working at a higher intensity, you are burning fewer calories and slowing your weight loss efforts down.  The idea of the fat burning zone was built upon the fact that you burn a greater percentage of calories from fat at a lower intensity than a higher intensity.  While this is true, you also burn less calories total and end up burning less fat than you would have if you would have worked at a moderate intensity.

To look at this mathematically, let’s say we have a 150 pound female who is walking at a speed of 3.5 miles per hour for 30 minutes.  During this time she is burning calories and 30% come from carbohydrate stores and 70% comes from fat stores.  Later in the week the same 150 pound female is running 6 miles per hour for 30 minutes and from her total calories is using about 60% from her carbohydrate stores and 40% from her fat stores.  Just looking at these numbers it is easy to see that she is burning more fat calories at the walking pace, but when we look at the whole picture we see something a little different.

On her walk, this lady burned a total of 130 calories.  From her calories, 70% were directly from fat so that means she burned a total of 91 calories from fat.  On the run she took later, she burned around 350 calories.  Since she was running, she was burning 40% of her calories from fat so we find that she burned 140 calories from fat on her run.  Here you can see that she ended up burning more calories total on the more intense run rather than on the walk, and she ended up burning more fat calories as well, promoting her goal of fat loss.  Therefore, you should aim to work at a moderate intensity, one that you are only able to speak in short sentences, and disregard the “fat burning zone.”  Training in the higher intensities trains your heart to be healthy along with helping you achieve your fat loss goals. 

For the rest of “The Simplified Science of How to be Healthy” go here.