archive

Sunday, January 25, 2009

Second Place

Dig this! Aerobics is groovy, man. It's far out. The happenin' 70s thing, for the dude on the go! So boss! Right on! Dy-no-mite! Red rocket man! Totally out of sight! Shazbot! Kiss my grits! Let it all hang out! Jive turkey! Sit on it! Plop plop fizz fizz. I can't believe I ate the whole thing! Keep on truckin! Disco lives!

Aerobics. It's not what it used to be.

Not a bad thing. It's just not the only thing. Not even the main thing. Unless you live in the Kalahari, in which case covering long slow distances -- LSD -- is a requirement for survival. But you don't, and it's not.

For most people, aerobics workouts plateau after about 8 weeks. After that, it's just burned calories, but at a reduced rate, because the body has become efficient at that narrow activity. Being efficient is a good thing, if the thing is an adaptive trait. Flying south for the winter, say. But that's not why people do aerobics. So do your 8 weeks, then do an occasional maintenance workout for that skill. It is, after all, a skill -- and it would be a shame to lose a skill. But otherwise it's just sucking up your time. Sorry to be the bearer of bad news. If aerobics is your thing. Dude.

Aerobics makes you slower. ... Aerobic make you slower? ... Whateverrrrr. Muscle cells adapt to the activity they are most required to do. Spending a lot of time in low-grade calorie burning makes fast-twitch fibers (required for power and strength) function as slow twitch fibers (weak endurance). The expression of your genetics changes. One myosin protein type within the cell is selected over another. Regarding athletics, most people would rather be fast and strong, than slow. You get good at what you practice. Practice being slow, and you will be.

Aerobics generates a higher volume of free-radicals, than more strength-focused workouts. Free radicals are aging. Highly aging. The longer you run, per workout or habitually, the greater the flood of oxidative pollution in your system. This depletes your supply of antioxidants. Bad all the way around. Always at your back you hear Time's winged chariot racing near. You can run, but you can't hide. Damage equals age.

Aerobics stresses the, uh, stress hormones. Testosterone goes down, cortisol goes up. Bad combination. Testosterone adds muscle. Cortisol dissolves it. It's a bad thing. Your body doesn't know you're working out. It thinks you're fleeing a wildfire. There's a difference between controlled exercise stress, of pressure alternating with rest, and prolonged flight. The result can be adrenal fatigue, symptoms of which are: fat retention, allergies, arthritis, flus, fearfulness and anxiety, depression, lack of focus, forgetfulness, insomnia, tiredness and fatigue. This stress, added to workaday stress, is a formula for fat retention. Counterproductive, it can be.

Sprinters have less fat than marathoners. Go figure. On the other hand, it makes sense. Fat is the fuel marathoners use. Not so, with sprinters, for whom fat is unwanted ballast. Intensity burns fat. Intensity is high heartrate, not miles plowed. Jogging for an hour will burn more calories than running 10 sprints of 20 seconds -- but over the next two days, the sprinter will burn more calories. Go figure. It's the ramped up metabolism. In a 1997 study (by I. Tabata et al.), joggers improved aerobic capacity by 10%, with zero% anaerobic gains. Sprinters improved aerobic capacity by 14%, and anaerobic by 28%. Hmm. Intensity burns fat.

Jog? Sure, why not. Generally, not more than 45 minutes at a time. More than that may raise cortisol output to detrimental levels. Cortisol, a stress hormone, breaks down muscle protein for its glucose. Your body figures it's more important to escape the danger, than to keep muscle that isn't helping you run away. A live to fight another day sort of strategy. Very sensible, if you're fleeing tigers. You, alas, are trying to flee your fat behind. The wrong thing is being shrunk. And you did just see the numbers. Intense intervals increase aerobic capacity 4% more than does jogging. Less time, greater benefit.

Still, something is better than nothing. Jogging is generally better than sitting, only. And if you won't do the better thing, at least to a thing that's better than nothing. A workable compromise, eh? Sort of like the way we manage to live in the world. Perfection is not required -- just effort.


J

2 comments:

Will C. said...

"Your body doesn't know you're working out. It thinks you're fleeing a wildfire."

I think your body does no such thing without the added element of the fight-or-flight mechanism...lacking in most work outs.

Unless of course you're Jack, who only does his aerobics in front of packs of wild, rabid wolverines. ;)

Jack H said...

In terms of physiological response, your opinion is uninformed. How sad for you. In terms of emotion, you would be correct. This must be what you mean by "flight-or-fight" mechanism.

Here's the clue. There is no exercise benefit in the accelerated heartrate of emotion. Major muscle mass must be engaged, for the hormonal benefits to accrue. These benefits accrue with or without the emotion. QED.

Next.

J