If you have been on the fitness train for an extended period, you must have come across the term “Cardio”. And depending on which camp you belong, you may either love or hate it or have a love-hate relationship with it.
Anytime I hear people talk about how they don’t like cardio or how they see it as a necessary evil; I always wonder if they understand the meaning of the word.
Cardio is more than running
For many people, Cardio means, running! But that is incorrect. Yes, running is a type of cardio exercise, but Cardio is much more than running. A cardio exercise is any exercise that requires the movement of the large muscle groups.
To explain in a simple term, a cardio exercise is any exercise that requires that you move your legs, arms and torso at the same time.
This type of exercise places a higher demand on the organs that are responsible for respiration and nutrients transportation. For example, when you stand up to move to the beat of Shoki at that party, you are doing a form cardio. (Apologies if you are not a Nigerian. Shoki is a type of dance step in Nigeria).
Like I did explain in the first article in this series, cardio-respiratory fitness is the ability of the heart, blood vessels and respiratory system to supply nutrients and oxygen to the muscles and the ability of the muscles to utilise fuel to allow sustained exercise. Whether a person is walking or dancing, the heart, blood vessels and the organs of the respiratory systems are working in concert to deliver nutrients and oxygen to the working muscles.
How fast and far a person can go, depend on the efficiency of the cardio-respiratory system. A fit person can exercise for a relatively extended period without unnecessary tiredness.
Types of cardio exercises
Any exercise that involves the movement of large muscle groups is referred to as a cardio exercise. The more muscle groups a person can recruit during a particular exercise the more demand the exercise is will on the cardio-respiratory system. Walking, jogging, running, dancing, skipping, swimming, kickboxing, step aerobics, and cycling are all cardio exercises.
Intensity versus impact
Exercise places a particular kind of stress on all the systems that are involved in human movements (i.e. cardio-respiratory system, musclo-skeletal system, and neuromuscular system). This stress is referred to as intensity and impact. It is important to know that there is a big difference between exercise intensity and exercise impact.
Intensity refers to the demand of exercise on the cardio-respiratory system (heart, lungs and the associated blood vessels), while impact refers to the demand on bones and joints. An exercise can be high intensity and still be low-impact, but all high-impact exercises are high intensity in nature.
Exercise intensity is relative
Exercise intensity is also relative. An exercise that is considered to be high intensity by one person may be considered as a low or moderate intensity by another person, depending on the individual’s fitness level.
High impact exercises like running and jumping are not gentle on the joints of lower extremities. Therefore, you should be careful with them if you have issues with your hips, knees, and ankles.
Low-impact exercises like walking, cycling and swimming are gentle on the joints and can provide moderate to high-intensity challenge for the cardio-respiratory system.
An exercise program does not have to be hard to be effective. Intensity is a matter of the heart, and it is relative.
The fat burning zone
If you use cardio machines like the treadmill or stationary bike, you’re familiar with the term, “fat burning zone.” It sounds like a sweet zone to be if your training goal is to lose fat. After all who doesn’t want to live forever in a zone where they can burn fat all day long.
The Fat burning zone is not a good zone to be during exercise if fat loss is your goal. To maximise fat loss, you want to burn lots of calories during your workout and continue to burn more calories hours after your workout is over. High-intensity training, especially high-intensity interval training, has been shown to be an effective way to achieve this.
Steady cardio has its place and benefits in health and fitness, but interval training has been proven to be the winner as far as fat loss is concerned.
High-intensity interval training (HIIT)
High-intensity interval training alternates short bouts of high-intensity exercise periods (referred to as the work phase), with low-intensity exercise periods (referred to as the rest or recovery phase).
High-intensity interval training gives you a bulk for your time and offers various health and fitness benefits. One unique advantage is HIIT’s effect on Excessive Post Oxygen Consumption (EPOC) which is also known as the “Afterburn Effect”. After an exercise session, oxygen consumption (and thus caloric expenditure) remains elevated as the working muscles try to return to pre-exercise state. This translates into higher and longer calorie (fat) burning hours after exercise has stopped.
Steady cardio, also known as aerobics or endurance training, is any cardio exercise that can be done at a constant pace for 30 minutes or more.
Effects of body composition
I hope you still remember the definition of body composition from the first article in this series.
Both methods of cardio training have their benefits, but their effects on body composition are different. Take a look at the physique of a sprinter and that of a distance runner and you will under the different effects both training methods have on body composition.
A sprinter training regimen comprises of short bouts of activities followed by recovery periods (a form of Interval training) while the training regimen of a distance runner mimic her/his sport (long and steady training).
“Form follows function, the form your body is going to take will depend on the functional demands you place on it.”
How to measure cardio intensity
There are different ways you can measure the intensity of your cardio exercise. You can use a heart rate monitor, you can check manually (this method is not recommended if you don’t know how to find or check your pulse), and you can use a simple method referred to as Rating of Perceived Exertion (RPE).
Measuring exercise intensity with RPE does not require the use of any watch or equipment, all you need to do is to listen to your body as you exercise.
Use the Rating of Perceived Exertion (RPE) to determine your workout intensity
Level 1: Sitting down doing nothing
Level 2: I want to smell the roses
Level 3: I am taking a leisure stroll
Level 4: I can do this all day
Level 5: This pace is right for me
Level 6: Now I am moving
Moderate to high intensity
Level 7: This is work, but I can handle it
High Intensity – Near your max effort
Level 8: This is serious work
Level 9: I don’t know for how long I can hold this
High Intensity-Your max effort
Level 10: Somebody, please call the doctor (Don’t ever get here)
Test your cardio-respiratory fitness
Yes, we are using running for the test because it’s the only form of a cardio-respiratory test protocol that can be easily self-administered. You will need a timer for this test.
Step 1: Map out a 1.6 km (1 mile) distance.
Step 2: Warm up for 5 minutes to bring your heart rate up.
Step 3: Start your timer and walk, run or jog the distance as fast as you can. Check your timer when you get to the finish line.
What your score says about your cardio-respiratory fitness
If you cover the distance in 12 minutes or less, you have good cardio-respiratory fitness. If you do it in 13-15 minutes, you are okay, but there is always room for improvement. If your time is more than 15 minutes, you need to work on your cardio-respiratory fitness.
Note: You can also do the test on a treadmill follow the same protocol but raise the treadmill at 2% incline in other to get the same resistance of running on the ground.