CARDIO....some people love it, some people hate it. But what is it REALLY!?!
Most of us consider "cardio" to be "aerobic exercise."
AKA when we think CARDIO we think steady-state exercise we do for 30 minutes or more, most often done as running or cycling.
We've even come to call the equipment we often use for steady-state exercise, such as treadmills, bikes, ellipticals or StairMasters, as "cardio equipment."
But CARDIO isn't just aerobic exercise or limited to those few pieces of equipment.
By thinking of cardio as only aerobic exercise, we can even prevent ourselves from creating a well-rounded training program that provides us with the full benefit of cardiovascular activity.
So what truly is "CARDIO?"
Cardio is actually ANY cardiovascular activity that increases heart rate and respiration. It is activity that can address one, or even all three of our Energy Systems NOT JUST THE AEROBIC ENERGY SYSTEM! (It's why even strength training can have cardiovascular benefits!)
And it is important that we realize how to work all 3 Energy Systems to get the full benefit of cardio and improve the function and the performance of our hearts, lungs and circulatory systems!
Cardio is not only the jog or walk, but also the sprint. Heck, it's every intensity even in between!
So you may now be thinking..."Ah yes! HIIT is also cardio!"
And HIIT most definitely is.
You may even be thinking that it is BETTER cardio.
And yes, HIIT, or all the variations of Interval Training, can provide the same results as steady-state cardio but in way less time, making it a great alternative for those of us short on time. (Studies have even shown it can actually lead to greater fat loss and metabolic benefit.)
HOWEVER, true HIIT again only focuses mainly on one energy system... True HIIT focuses on our ATP-PC or Anaerobic A-Lactic System.
Of course, you could then ask...
What is "true" HIIT?
True HIIT is just one form of Interval Training yet many of us, myself included, often use it to describe all interval training where we are working at a high intensity.
True HIIT is that maximal performance, our true 100%, every single time with enough rest that we can actually perform at a maximal level. Usually at least 2-3 times the work at minimum with sometimes up to 5 times the rest.
Interval Training though refers to ALL intervals with varying work to rest ratios that, while we may work at a high intensity, may actually be lower than our "true" 100%. Work to rest intervals for this can range from 1:5 to 5:1!
So not only do we need to recognize that HIIT and Interval Training are different but that CARDIO should encompass ALL of these cardiovascular conditioning tools.
(And if you call Interval Training "HIIT" no police will come after you, but I think it is important we do understand there is a difference even if we ignore there is one often when talking with clients. I do think we are allowed to sometimes use terms that will speak to what our clients are looking for, but that is another conversation!)
If we actually want a strong and healthy cardiovascular system we need to work all 3 Energy Systems. That means using a variety of intervals from steady-state to HIIT!
So what are the 3 Energy Systems we need to work to improve our cardiovascular health?