To talk about cardio, short for cardiovascular exercise, we must begin by understanding what these words mean. Cardio is a word that means “pertaining to or relating to the heart.” Vascular is “relating to, affecting, or consisting of vessels.
The most important detail regarding cardiovascular health is knowing your resting heart rate. This is the natural rhythm of your pulse when you are resting. Our pulse is a contraction, a bit more electrical than ordinary muscles but a contraction nonetheless, which would suggest that the heart is a muscle, and it is, but it is also much more complex than an ordinary muscle. Science defines the heart as a muscular organ.
We can’t measure the strength of our heart in the same way we can measure our chest by how much we can push up, or press. We can only measure where it starts at rest, the highest rate it can maintain at maximal effort, and how quickly it recovers when exertion is over. Knowing your resting heart rate is critical to understanding your heart health and accomplishing your cardiovascular training goals.
The heart tirelessly pumps blood into vessels and the circulatory system for your entire body and it is smart enough to organize the flow of oxygenated blood on one side, separate from the de-oxygenated blood. A normal adult resting heart rate is somewhere between 60 and 100bpm. A baby in the belly, somewhere around 8 months beats at around a resting rate of 130 to 140bpm. This is about the same as my Chihuahua! A hummingbird has been recorded to have a resting heart rate of 1,260! One would say that it doesn’t make sense that a tiny hummingbird’s heart has to beat that many times when the bird only weighs 4 grams. How could it need that much pumping when it’s so tiny? But what is obvious yet counter-intuitive is that, the smaller the body, the smaller the heart.
When trainers and cardiologists urge you to begin cardiovascular activity, i.e. stationary bike, swimming, walking, etc. it is for good reason. Your heart needs as much exercise as your legs, hence the discrepancy as to whether the heart is a muscle or organ? We don’t work our liver or kidneys, do we? Through cardio, the heart becomes stronger, and increases its size and cardiac output. Cardiac output is the amount of blood flow multiplied beats per minute. (BF x BPM)
The heart, like all other muscles, need rest. It beats and then takes a pause and then beats again. This is the pulse we listen for when taking our resting heart rate. You can count all beats within a minute, or you can count beats for fifteen seconds and multiply by four. It is important to understand that in order for an accurate read, one must truly be at rest. Naturally, the longer the pause between pumps or beats, the lower the resting heart rate. Those who have high resting heart rates have a heart that is working harder and with fewer rest periods.
- Elevated heart rates are a symptom of an overworked heart, and this translates into less efficiency, a susceptibility to dysfunction, failure, and fatigue. The heart fortifies the entire body AND is the last muscular organ you want to be overworked and under rested.
- A lower resting heart rate indicates a strong heart, either naturally or one that has adapted to the demands of cardiovascular exercise and has learned to increase cardiac output and enjoy a rest between beats.
How often should someone engage in cardiovascular exercise?
There should be an element of cardio in each and every routine you create. You can have cardio/aerobic activity between resistance exercises or weight lifting, or days where you strictly do cardio/aerobic exercises, or resistance exercises that incorporate an cardio/ aerobic element into them. There is no one answer as each person has specific goals they are training for.
What kind of goals can be achieved by cardiovascular activities?
- Increasing the overall cardiac output of your heart
- Increasing the size of your heart and ventricles, which will allow for continued elevated cardiac output, not just during exercise, but into the future of your cardiac health.
- Fueling cellular respiration processes in the body with fat cells, training them to use more than just carbohydrates as an energy source.