The physiological benefits of aerobic training, also known as resistance or cardio, include improvements in tidal volume (amount of air moved by the lungs), blood volume, and stroke volume (amount of blood moved by the heart per beat). It also increases the number of capillaries and the number and size of mitochondria. All of these contribute to the body’s ability to transport oxygen to the working muscle.
Recent research has shown that cardiovascular exercise, but not strength work or interval training, can enlarge the brains of rodents.
Okay, forget about how much that last part sounds like the premise of a 1950 sci-fi movie. Let’s look at some other research.
A long-term study followed 1,583 middle-aged men and women with no personal history of dementia or heart disease for two decades. Before-and-after tests performed 20 years apart showed that those who had stayed in shape tended to have larger brains, while the poorly conditioned participants had lost gray matter.
Holding onto gray matter prevents cognitive decline and lowers the risk of dementia. However, no specific type of exercise was explored in that study.
And that’s a perfect introduction to the long-running debate on cardio and high-intensity interval training (HIIT).
HIIT fans always stack the deck
Let me be clear: I have nothing against high intensity intervals. I use them often in my own workouts and when teaching.
But an interesting thing happens when staunch proponents of HIIT compare the relative benefits of HIIT to standard cardio.
They tend to cheat.
In the hands of the HIIT fanatic, the word “cardio” has become a code for boring exercise at the lowest intensity levels. It should come as no surprise that the benefits, if any, of these unconvincing workouts outweigh the benefits of HIIT.
And no one challenges the criteria. So let’s challenge them with just a few simple facts.
You can go hard and long
It’s not true that intense training should involve short intervals of, say, 20 to 60 seconds. If you train well aerobically and seriously enough to achieve the aerobic benefits mentioned above, you can maintain a high level of work for quite some time.
Elite marathon runners, for example, run at a pace of more than 5 minutes per mile for 26.2 miles. Most people would find it difficult, if not impossible, to run a 5 minute mile. It is a fast pace. Elite marathoners do it for a couple of hours.
As stated by Matt Fitzgerald, well-known marathoner, trainer, and author of several books and articles, “Well-trained endurance athletes don’t really have to slow down much as they increase the duration of their efforts. Read magazines on elliptical trainers.”
Can’t we combine cardio with HIIT?
The training combination that appeals to me the most is a set of about 8 intense intervals in a long moderate or moderately high intensity workout.
However, it is not just my personal preference. There is evolutionary evidence that this form of training is precisely what we always should have done.
In his book Born To Run, Christopher McDougall reveals the combination of morphology, paleontology, anthropology, physics, and mathematics that led to understanding how humans became the best distance runners in the animal kingdom.
There is no way this article can do justice to McDougall’s fascinating and detailed description of the appearance of homo sapiens on Neanderthals (they were parallel species) and the evolution of humans as supreme hunters hundreds of thousands of years before creation. of the tools we associate. with hunting (spearheads, bows and arrows).
Some of the evolutionary changes include upright posture to allow deeper breathing and limit retention of solar heat; the ability to release body heat through sweat, rather than panting like other mammals until they must rest or die of hyperthermia; and the ability to accelerate once the hunted animal has been exhausted.
The human “persistent hunting” was a combination of primarily endurance running, plus some short sprints. Humans evolved to run in conditions that no other animal can match, and it’s easier for us.
Good at stamina (for a long time)
Endurance athletes can generally continue into what is considered old age in other sports. In activities like distance running, they can still outperform teens or 20-year-olds until their mid-60s.
When workouts are always high intensity, there is likely to be overtraining, a lack of full recovery, and a high incidence of injury.
Exhaustion after constant high intensity work makes it feel like heaviness, rather than something to look forward to every day. Why not exercise in a way that you enjoy in the long run?
Endurance athletes of other types show similar results. Master riders age 50 and older often outperform younger riders.
So the choice isn’t really between short, intense intervals and long, slow cardio with a magazine. The right kind of training included both.
Cardio, of course, should be hard enough to cause a training effect, not to help you catch up on your reading.
That perfect combination is effective, enjoyable, sustainable in the long term, and totally in sync with our evolutionary nature.