On mitochondria and thoughts on aging
What are your thoughts on aging? Mitochondria?
When you think about aging, what comes to mind?
Do you think of wisdom? Or maybe creaky knees or downsizing? Or maybe you see aging as full of opportunity? 
Lately, when I think about aging, mitochondria pops up for me. Mitochondria? Yes. That’s right.
And it all has to do with why I’m teaching MOVEit (interval training).
Mitochondria and a Theory of Aging
Mitochondria are considered to be the “powerhouses” or energy generators of the cell. Without well-functioning mitochondria, we are without energy.
Mitochondria extract energy from the nutrients in our food and transform it into a chemical called ATP (adenosine triphosphate for you acronym meaning-seekers!).
ATP is the energy “currency” of the cell which is responsible for powering all of the cells’ metabolic activity. You might think of food-derived nutrients as “crude fuel” and ATP as the “refined fuel” that helps the cells do things like break down nutrients to be absorbed.
For a variety of (extremely complex) reasons, as we age, the energy-generating capacity of our cells’ mitochondria slowly decreases. This means that our cells become less and less effective at converting and using energy.
And so aging occurs.
Can we boost our mitochondria as we age?
As I’ve been learning more about why MOVEit is such an effective fitness practice, I’ve read over and over that the cellular benefit of exercise has only recently been discovered.
While we know that exercise is good for our heart and lungs and other organs, understanding how the building blocks of those organs (i.e., the cells) benefit from exercise is only now being discovered.
A study, recently published in Cell Metabolism found that interval training affected not only the participant’s cells, but also their genes.
Not only that, but the genes that were working differently after interval training are believed to influence the ability of mitochondria to produce energy for muscle cells.
In fact, the subjects who did the interval workouts showed increases in both the number and health of their mitochondria — this finding was particularly pronounced in older subjects.
How does interval training work?
In every MOVEit class, we challenge ourselves to get into a period of “enough” between 3-6 times during the class. “Enough” is defined as a period of short duration, high intensity movement lasting anywhere from 30 seconds to 2 minutes.
The period of “enough” is when we use movement to get to our maximum aerobic capacity – the point where we literally run out of oxygen supply for the muscles. When we get to this place of “enough”, our bodies then rely on other energy systems – anaerobic metabolism – which ultimately increases the efficiency of the cell.
Because of the potential to build up lactic acid during strenuous activity, active rest intervals are interspersed into periods of “enough” so that we can again return to maximum effort/”enough”.
Active rest periods also allow the muscles and the central nervous system to recover and come back with a punch during the next period of “enough”.
View a MOVEit class in action here.
Curious and want to read more?
Look here and here and here and here!
(updated Apr 2, 2020)