Your Body is a Fortress, Part 10 – Training for Old Age

Warning: this post is longer than my usual ditties. The articles in my Your Body is a Fortress series are meant to be more meaty with heft and breadth. So, come back when you have more time if you’d like to learn more about your beautiful body electric.

I enjoy reading research results that support or explain something I intuitively know to be true.

I generally don’t need research results to convince me of things, but I love it when I see a study about something that makes me think, “Ah-ha! That’s why when I do this I feel that!” Yes! Especially research about the impact on our bodies of what we eat, do, or think.

It was more fun when it was ME doing the researching, but since I can’t to that anymore, reading the current research keeps me up to date. As I eluded to above, one of my favorite moments in scientific discovery unfolds when I learn why something I feel or intuitively know to be true can be demonstrated in a scientific experiment.

For example, if I eat too much fat (potato chips, ice cream, etc.) I often feel kind of gross for awhile. It tastes good and is fun every now and then, but to learn WHY ingesting fat has that effect was so interesting. It’s really quite simple, it’s because fat takes much longer to digest than protein or carbohydrate, and is also why it produces that prolonged feeling of satiety. Unsaturated fats in moderation are a GOOD thing, though, so don’t give them up altogether. I could go even deeper into the molecular structure and our physiology to describe why it takes much longer to digest fat, but I’ll spare you the details so I can get to the point of this post.

On the subject of eating, back when I used to be an athlete (before Ms. MS took over shop) I trained a lot and I could eat a lot. I had to eat a lot to fuel my body. I’d often workout before work, join a Master’s swim group at lunch, and then train again after work every day and on weekends, too, with the occasional recovery day.

And, you know what? Working out made me feel good. It helped me combat depression, it helped me get though a painful divorce (is there any other kind?). And, I often joked around with my clients that I worked out to prepare for old age. Seriously, I’d say, “Yup, just another day of training for old age.”

I’d usually get a few chuckles.

For me, it wasn’t about living to be 110, it was about staying independent and mobile as long as possible.

So, fancy me doing some reading recently at the online Public Library of Science and BAM! Awesome! I find a study delving into a possible explanation why exercise helps to combat “old age”, and more specifically, how exercise fights the negative effects of stress.

As a side note, I love PLOS. It’s an open-access resource for publishing scientific research, legit, rigorous, peer-reviewed, and open to the public. I could write a whole post on the importance of this communication method, but I’ll save that for later.

One of the first things I notice about a scientific article is if I recognize any of the authors. BINGO, Elizabeth Blackburn is one of the authors of this report and helped with the study design. She’s an accomplished scientist at UCSF, Department of Biochemistry and Biophysics, and she was also named one of TIME Magazine’s 100 most influential people in 2007. Dr. Blackburn has also won awards that are akin to being on the US Olympic team. Suffice it to say, she rocks.

The Power of Exercise: Buffering the Effect of Chronic Stress on Telomere Length

In this publication by Eli Puterman and colleagues including Dr. Blackburn, the authors state, “Vigorous physical activity appears to protect those experiencing high stress by buffering its relationship with TL [telomere length].”

What the heck is a telomere?

Good question.

It’s important to understand these things before we can understand why it’s so important to protect them. A telomere is kind of like a helmet for your chromosome ends (see white tips in image of actual chromosomes above). A telomere is a complex of DNA and protein that caps the end of the chromosome—everyone has 23 chromosome pairs (46 total) per cell, except for gametes which only have 23 chromosomes, remember?

Anyhoo, these caps contribute to the chromosome’s stability. As cells divide and replace older cells, a piece of your cellular machinery (called ‘telomerase’) actively replaces these caps to protect the DNA. Basically it behooves the cell to have high-performing telomerase activity. Sure, there’s a short “buffer” at the end of the chromosome, but as cells divide, if the DNA looses it’s protective cap, it can shorten to a critical length. That’s when things can go wrong.

At this stage, the cell can basically go to sleep and stop dividing. What then? A host of problems can begin, such as immunological problems signaled by the sleeping cells, which can promote heart disease, diabetes, and eventually you’re pushing up daisies too soon.

Importantly, telomere shortening has long been associated as a marker for biological aging.

OK, get this, short telomeres have been reported in people with high psychological stress, too.

Puterman and colleagues were familiar with the phenomenon other researchers have demonstrated along with this tasty nugget: endurance athletes have longer telomeres! (Excellent!)

With this data in hand, the researchers wanted to understand if stressed but physically active people would be protected from telomere shortening compared to sedentary (and stressed) controls. So, they designed an interesting study looking at this hypothesis. If you want to read the nitty-gritty, I suggest reading the original article.

To summarize, the authors state:

“…physical activity was able to protect those experiencing stress by buffering its relationship with TL [telomere length], as hypothesized. Our findings support the physical benefits of activity, and, interestingly, map well onto Centers for Disease Control (CDC) recommendations for amount of physical activity required to sustain a healthy body (75 minutes of vigorous exercise per week). … In the present study, we were able to rule out potential factors as alternative explanations for both the stress-telomere association and the buffering potential of physical activity.”

So, basically the researchers’ hypothesis was supported by the data they gathered from the study.

In their final remark, the authors also suggest, “It is reasonable to conclude that exercise should be strongly advised and prescribed to people reporting high levels of psychological stress.”

However, they also mention that highly stressed people are also inherently less likely to exercise. And I *get* that, too. Believe me, I do, more than you know. (My MS severely limits my ability to exercise.)

I’m not here to make anyone feel bad for not exercising. We all can only do what we can. I’m only here to say I’m pleased the accumulating research undeniably supports that exercise rocks when it comes to delaying aging, combating depression, dealing with the physical detriments of stress, and even improving cognitive function.

The next time you’re staring at your swimsuit with a frown or deciding between that extra cup of coffee or a brisk walk, please remember all the good that comes with exercise. Deal?

I enjoy reading research results that support or explain something I intuitively know to be true. Maybe we should trust our intuition more often?

Now, get out there and sweat! Workout to train for old age.

[Thank you to the authors of this publication for sharing this great study! I've shared quotes in this post courtesy Creative Commons license from PLOS ONE, a peer-reviewed journal of the Public Library of Science. Telomere photo courtesy Creative Commons license via US Department of Energy Human Genome Program. Photo at top of post by Maria Keays via Creative Commons license.]

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