06/13/2013 02:56 pm ET Updated Aug 13, 2013

DARE to Be 100: Why Is Physical Activity Good and Inactivity Bad for Everything?

Your heart, your arteries, your bones, your muscles, your blood cholesterol and blood sugar, your immune responsiveness, your intellectual competence, your humor, your aging process all heed the imperative "use it or lose it." How can this be? It clearly is not the result of a single component advantage. It must be secondary to a systemic effect. What kind of effect?

Earlier I wrote a piece for the Saturday Evening Post entitled "exercise as the oboe's A." As a committed symphony orchestra enthusiast, I, like you, have witnessed the mayhem that occurs onstage before the concert starts, much blaring, thumping and general discord until the concert-meister emerges and out of the bowels of the orchestra, the oboeist plays A. All of a sudden the entire ensemble comes to order, and rhapsodies emerge. All of the instruments, the organs, get in tune with one another, and beautiful music, health, comes forth.

The reedy A of the oboe is what exercise does for all of the body's gene instruments. This energetic signal keys the switches and all come into a harmony. They join in a concerted performance. Without the signal they would all be on their own.

Each individual switch, gene, (instrument), is not the critical issue. Rather it is how it is played. This is similar to card games. What matters is not the individual cards but how they are played. The master term for this is epi-genetics, how the gene is keyed. Different energetic cues act as gene switches. Varying environmental stimuli, chemical, mechanical, spatial, temporal serve to activate the process.

But the one I reference here is thermal. It is recognized that temperature change acts as a potent signal for gene expression. For example, the gene switch, CTP19 on CHROSOME15 controls the production of the enzyme, aromatase. When in the turtle the temperature goes up, the gene and its enzyme go up and the turtle is a male, and vice versa. Temperature is a generic prompt for gene expression.

My suggestion that the reason why exercise is good for everything has to do with the fact that exercise acts to up regulate, to express the favorable genes of the mitochondria. These are the key critical intracellular particles that control the activity of all the central body functions that in turn determine exercise's universal benefits.

As we exercise the mitochondria of our muscles and many other body components heat up as the result of increased blood flow. The HOT MITOCHONDIA are the reason exercise is good and inactivity is bad for everything.

Warm up your mitochondria and get healthy. As you learn this lesson do not forget Bortz's law , "it is never too late to start, but always too soon to stop."

For more by Walter M. Bortz II, M.D., click here.

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