physiology lesson?

amandaeve

I am curious about the physiology of the body as it ages with regard to fitness. It's obvious 60-year old athlete can't perform at the same level as a 20-year athlete, but why? I've been attending various aerobic fitness classes for 20 years. I'm just as fit as I was 20 years ago (I could even argue more fit), but I simply don't have the same bounce or energy I did then, and "pushing" myself to the limit seems harder and more painful with every year. I assume something is changing on a cellular level. What is changing? Are the copies of copies of the cells in my body failing to replicate according to their genetic instructions? And how? Even if you progressively work out harder, as some point muscle mass decreases. I only understand how the body changes from the surface. One could spend their whole career studying this thing, so if anyone could dumb it down, share some scholarly articles, or share what process they find to be the biggest factor, I'd be curious to hear.

dandur

Oxidative stress (the rusting of our engines) and the shortening of telomeres (the copies of copies of copies thing you mentioned). Two major factors in the aging process. Search those and you'll get a much better picture of what's really happening. Very eye opening.

GlassAngyl

dandur wrote: »

Oxidative stress (the rusting of our engines) and the shortening of telomeres (the copies of copies of copies thing you mentioned). Two major factors in the aging process. Search those and you'll get a much better picture of what's really happening. Very eye opening.

And terrifying. I'd rather not contemplate my mortality..

amandaeve

Interesting. I found descriptions that linked oxidative stress and telomere shortening to the excess diseases (diabetes, heart disease, cancer, etc.). I'm assuming free radicals and shorter telomeres present universally across the body as we age (as opposed to a cancer that would be localized). I couldn't find an explanation to how that makes us slower, more tired, weaker, etc. Though, I guess I could just admit we deteriorate across the board as we age. I am only noticing changes with athletic performance, but I guess this universal degradation could also explain poorer vision, hearing, skin elasticity, healing from injury, brittle/thinning hair, difficulty learning new information and all the other symptoms of aging that haven't bothered me yet. It is terrifying. I feel a compulsion to "seize the day" before I feel and function worse, but I balk under a society that only values people who work long hours and suffer until they retire.

AnnPT77

amandaeve wrote: »

Interesting. I found descriptions that linked oxidative stress and telomere shortening to the excess diseases (diabetes, heart disease, cancer, etc.). I'm assuming free radicals and shorter telomeres present universally across the body as we age (as opposed to a cancer that would be localized). I couldn't find an explanation to how that makes us slower, more tired, weaker, etc. Though, I guess I could just admit we deteriorate across the board as we age. I am only noticing changes with athletic performance, but I guess this universal degradation could also explain poorer vision, hearing, skin elasticity, healing from injury, brittle/thinning hair, difficulty learning new information and all the other symptoms of aging that haven't bothered me yet. It is terrifying. I feel a compulsion to "seize the day" before I feel and function worse, but I balk under a society that only values people who work long hours and suffer until they retire.

There are various degradations, sure. But all I have to do us look around me to see that I have significant influence over the rate and extent of those degradations.

My active friends who eat nutritiously visibly "age more slowly" (for lack of a better way to put it) on average than the inactive ones who eat poorly. They are more independent, more nimble, injure themselves less frequently, have better endurance, get sick less often and less severely then recover faster, bounce back from any necessary surgery more quickly, have fewer chronic conditions, require fewer prescription drugs - I could go on and on.

To the extent I've seen folks reach the end stages of life, the active, healthy eaters tend to experience a much shorter and later period of acute decline.

I don't really see the point of worrying about the "we're all gonna decline and die" part, since we can do zip about it other than those healthy habits. To me, it makes a lot more sense to focus on the things we can do - the healthy habits - then just strive to enjoy the time we've got . . . and I don't much care whether society values me or not; I value me.

I didn't always feel this way, let alone act this way, I admit . . . but since becoming a cancer widow at 43, and a stage III cancer survivor at 45 - 17 years ago - I pretty much have.

Life is too short to waste on fretting about how short life is.

NorthCascades

I don't know if we (humans) understand it on that level or not. I sure don't. Cars Beaver the same way, probably all complex machines do. And we're they most complex of them all. But, beware of analogies, we might be like cars in some ways but very unlike then in others. We evolved to protect our offspring, and our usefulness ends when they can take care of themselves.

amandaeve

Words of wisdom, @AnnPT77. I am lucky to have known great role models for aging; a friend who started running marathons at age 70, a paddling guide in her mid-60s, a solo backpacker (https://www.amazon.com/Still-Going-Strong-Backpacking-Adventures/dp/0692776400). But everyone refers to this sort of indiscriminate pain of aging..and that scares me, especially when I feel pain. Still, you are right. Sorry for you and your spouse's cancers, but your strength shows in how you write. Your positive outlook is inspiring

JeromeBarry1

Aubrey de Grey is THE authority on it. https://www.ted.com/talks/aubrey_de_grey_says_we_can_avoid_aging

Dr. de Grey mentioned that RNA interference was only discovered a few years ago, and I was reminded of something.
It's a true statement I make: I once had a workplace colleague, a woman, whose college boyfriend had already invented the PCR, the polymerase chain reaction.

Call me a name-dropper if you want, but this only illustrates how very infantile is our human understanding of aging. I chose that word well. Infants are young and learning fast.

The t.o.r.r.e.n.t of discoveries following the development of PCR have included RNA interference and CRISPR/Cas9. The exponential growth rate in human knowledge of cellular function is real and increasing.

I used the periods in that perfectly decent word because the kittenator struck.