There are 2 different camps in the cardio department and both sides look at the other as if they are moronic and hurting the body more than helping it. Numerous times I've seen heated arguments back and forth between these two opposing groups. It's very interesting.
You have the endurance camp, the long steady state cardio people. The extremists of this group and the accepted norm of the general population believe that this form of exercise is superior to all others. They believe you should do it every single day or you'll die. (We're all going to die...get over it... maybe you can see where this is going)
The other side is where the different forms of circuit training and interval types live. They also think they have unlocked the secret to all things exercise related and that any other type of training is not only a waste of time but harmful to your body.
The funniest part is when each side starts throwing science back and forth at each other, both have plenty to back them up. From a bystanders perspective it resembles a more advanced version of monkeys throwing they're poop at each other. Is either right? Well, in my experience, accuracy rarely lives in the polar ends of any spectrum.
There is an interesting thing that very few professionals have figure out YET....I say yet because we're always improving. But that little thing is that both are correct. You'd be amazed if I said that in a room full of exercise professionals I would probably be burned at the stake.
This is a basic overview of how it works, you have your O2, that’s your 'aerobic base', where you are using a lot of oxygen to go for a long period of time. During 'aerobic base' training, aka steady state cardio, you are bringing your heart rate up and keeping it there for an elongated period of time.
Then there are alactics and glycolytics.
Alactics are where you are repeatedly going super hard, rest a little bit, super hard, then rest a little. Heart rate goes up and down during Alactic training.
Glycolytics are straight torture. By torture what I mean is you might go as hard as you possibly can for 20 seconds, then only 20 second break, possibly shorter, and then you repeat that over and over.
Glycolytics are awful, you don’t give your body time to rest. So your heart rate stays up pumping as fast and hard as it can to send nutrients to your muscles. At the same time those muscles are being bad ass, working hard with dwindling resources, all the while your brain creates a burning sensation that says STOP, STOP, Please STOP. This is called the grind. THOSE WITH GRIT DIG THE GRIND.
"Pain is weakness leaving the body" is an idiotic statment. Pain is a signal that something is wrong and needs to be listened to. The Grind however is different. The grind is where you push. The grind is extremely important.
So why are each of these significant and why are they both correct?
Something that is important to understand, humans ran their food to heat exhaustion for thousands of years. This is why we are so good at running at and maintaining a galloping pace. The reason we are able to do this is because we sweat better than any animal on earth (before anyone get's huffy, yes, other animals sweat, but not as well as we do, besides our big brains, it's all we do well). That, and sun only hits us on the top of our head and shoulders, which helps us regulate our body temperature. The other side of the coin is that for most animals the sun hits their entire torso, where all their vital organs are and they either pant to get rid of heat or they don’t sweat as well as we do. Ipso facto we were able to run them to heat exhaustion then walk up and club them in the head and have a nice meal.
Slight tangent, but think about this next time you see someone on a bike ride/jogging with a dog on a leash on a hot sunny day. Sad right. If you do this, please realize that dogs pant to get rid of heat and need to run-stop-run-stop. It's abusive to the animal.
Survival of the fittest is actually just the title of Darwin’s deal, the actual hypothesis was that the most adaptable survive. For instance humans didn’t adapt to the cold, at least not physically. I mean, I got a big ole beard, but this has nothing to do with being able to survive in the cold. Human hair is actually for sun protection. Nope, we did not adapt physically or we'd be covered in fur. But our ancestors were pretty smart and stole other animal’s skin that were able to survive and wore that around making us able to live in the cold.
How we train has much to do with our ancestors ability to survive. The reason you are able to run at such a wonderful galloping pace is because you are the offspring of those that were ABLE, and if you were able, you got to eat. If you got to eat, you could live long enough to reproduce, then your genes got passed on, which leads to us.
Its whoever is the most adaptable, not survival of the fittest. Humans are very adaptable because of our minds ability to create technologies to survive. The best able to survive passed on their genes, and that is why you and I and all of us ended up here.
Back on topic; why is steady state cardio still important? Why is it significant? Why are their two camps? Well, it is extremely good for your body to get your heart rate up and keep it up for an elongated period of time. It drives blood flood, it drives recovery, it has a mental component, it does good stuff for your heart.
Meaning, you literally recover from workouts faster. You're heart physically changes it's durability and ability to expand and pump blood easier just like your muscles and becomes much more efficient. There's an affect on your autonomic nervous system, this means your mood improves, you're more productive, have less stress and able to deal with stress better. Not to mention the ability to relax much easier. Crazy, I know, I know. It's pretty hard to argue with.
So where's the beef? The huge error comes when training the aerobic base too often.
To be very clear: One day a week is all you need.
Minimum affective dose wins every time. Doing too much isn’t necessarily a good thing, usually it’s real bad. Before the argument comes that was just posed from our ancestors. Yep, they did run food to death....but NOT everyday. We can maintain 'aerobic base' for 30-45 days. Wonder why? I don't know, how much time does it take to eat a wildebeest and go run down another one? So, no they didn't run their food to death everyday, they recovered and feasted for awhile between runs. Just like you need to do.
What about the interval stuff? What about alactic and glycolytic training? What are you supposed to do with that stuff if aerobic base training is so great?
Here is the things on why they are accurate. Alatics and glycolytics are the indisputable number one way to burn calories and burn fat. Any contention against this is pretty silly. Plus, they are way more fun (the last part is 100% opinion and completely contestable).
Our bodies are not set up to do alactics and glycolytics well. Performing things that we are not efficient at causes our bodies to perform more work, burn more calories and use it's stored energy differently…. And that reaction is extremely potent and extremely effective.
But we still need one day a week of 'aerobic base' training. ONE DAY. In a contest against people who are in speed sports and say “I can’t be getting slower by doing slow stuff”, one day a week does not effect it. One day a week is really good. How did I come to this conclusion? More of that science stuff…that’s how. Plus, walking is slow and you do that all day. You will be fine.
How often are we supposed to do alactics and glycoltics? Totally depends on what you are going for. Some people might only need one day a week, while others need more like two to three. But balance goes a long way. And especially after the age of sixteen, minimum effective wins out.
Why not just forget about aerobic base stuff and focus on the alactic and glycolytic training to get more out of that?
If you focus solely on your alactic and glycolytic training you are narrowing the effect of the training on your body because you don’t have the foundation. It works like this: If you have a small base then you are going to have less at the top. If we can build a bigger base, we can get more out of the stuff at the top. Keep it conceptual, you change the details based on the target, so if the target is fat loss, or performance you will change the details but not the concept. And the concept is if you build your base you will get more out of your alactic a glycolytic training, HOWEVER you only need 1 day a week of aerobic base training, which is, for most people between 120-150bpm for 30-45minutes.