Prolonged sitting is considered detrimental to health, but evidence regarding the independent relationship of total sitting time with all-cause mortality is limited. This study aimed to determine the independent relationship of sitting time with all-cause mortality.

… We linked prospective questionnaire data from 222 497 individuals 45 years or older … to mortality data …

During 621 695 person-years of follow-up …, 5405 deaths were registered…. The association between sitting and all-cause mortality appeared consistent across the sexes, age groups, body mass index categories, and physical activity levels and across healthy participants compared with participants with preexisting cardiovascular disease or diabetes mellitus.

Conclusions Prolonged sitting is a risk factor for all-cause mortality, independent of physical activity. Public health programs should focus on reducing sitting time in addition to increasing physical activity levels.

I’ve left out the numbers … briefly, if this study is correct and accurate, sitting for more than 11 hours a day measurably reduces lifespan compared to sitting for less than 4 hours a day. For the age group looked at, if you were a long-sitter you had a 40% greater chance of being dead within 3 years than if you sat very little in a given day. This does not mean a 40% chance of being dead … just 40% more than whatever it was. For lesser differences in sitting time, the difference in mortality risk is lesser as well.

I’m not sure how this translates into practical advice and I’m not sure this study alone provides enough information to answer that question. One way to think about this is as follows: If you sit many hours a day because of your job, how much of that sitting time do you need to change into standing time to make a difference, and can standing alone vs. moving around do the trick? Once that is established, perhaps one could create a standing version of one’s workspace.

I know what you are thinking: “I go to the gym for five hours a day so that fixes that problem.” Sorry, but no. Apparently (and this is not fully demonstrated, so this is something of a guess) it’s the sitting that hurts you, independently of the lack of exercise. Yes, those several hours a week of exercise helps you and makes you healthier, but the sitting itself, if we’ve got this right, is a bad thing, with negative effects, and if you do too much off that every day you’ll die sooner than otherwise.

Maybe.

Suggestions? Comments? Questions? Criticisms? Do you know of other research on this?

In rodents. So far.

The research team made obese rodents exercise was found to increase the amount of IL-6 and IL-10 protein levels in the hypothalamus, which in turn changed the threshold for the feedback system that ultimately releases insulin and leptin, which are the magic juices that seem to affect hunger and related system. Indeed, leptin has been seen for some time as a key to understanding weight control, has been implicated in various concepts like the “set point” and is linked to numerous rather complex systems. What may be happening here is that insulin and leptin levels act one way in the sedentary person and a slightly different way in the active person.

I’m going the gym.

Oh, wait, OK, I’ll finish this blog post first.

Here’s what the authors say about the study:

The hypothalamus is a brain region that gathers information on the body’s nutritional status and governs the release of multiple metabolic signaling molecules such as insulin and leptin to maintain homeostasis. Overeating and obesity are associated with insulin and leptin resistance in the hypothalamus, and recent studies provide an intriguing link between inflammation and dysfunction of hypothalamic insulin and leptin signaling through activation of IKKβ, a key player in immune response, and endoplasmic reticulum (ER) stress. This means that strategies to reduce the aberrant activation of inflammatory signaling in the hypothalamus are of great interest to improve the central insulin and leptin action and prevent or treat related metabolic diseases. Using a combination of pharmacological, genetic, and physiological approaches, our study indicates that physical activity reorganizes the set point of nutritional balance through anti-inflammatory signaling mediated by interleukin (IL)-6 and IL-10 in the hypothalamus of rodents. Hence, IL-6 and IL-10 are important physiological contributors to the central insulin and leptin action mediated by exercise, linking it to hypothalamic ER stress and inflammation.

And, if you want to know a LOT more about this process, click here to download a PDF primer on Exercise and Hypothalamic ER Stress.

You can read the paper, published in PLoS Biology, here.

Ropelle, E., Flores, M., Cintra, D., Rocha, G., Pauli, J., Morari, J., de Souza, C., Moraes, J., Prada, P., Guadagnini, D., Marin, R., Oliveira, A., Augusto, T., Carvalho, H., Velloso, L., Saad, M., & Carvalheira, J. (2010). IL-6 and IL-10 Anti-Inflammatory Activity Links Exercise to Hypothalamic Insulin and Leptin Sensitivity through IKKβ and ER Stress Inhibition PLoS Biology, 8 (8) DOI: 10.1371/journal.pbio.1000465

Like I said earlier, I returned from South Africa in similar or better shape than I left in. And I kept that level of exercise up for a long time, and kept in shape for a long time. Over the years, I had a couple of friends I’d go to the gym with on a regular basis. Amanda and I formerly did that quite regularly, but we have slacked off a bit.

But eventually, life got the better of me, and I started to slack off and go to the gym less and less often. Then, I got a job that actually did serve as a great excuse for not getting to the gym, and then I had some other excuse, then some other, then some other.

So right now I find myself in a similar situation as to when I first met Lenora. But this time, I don’t need a trainer, and the gym is one block from my house. What I need, rather, is the obsession. I need to get back the obsession with exercise that drives a person to the gym because it feels bad to have not been to the gym for a while.

This is not hard for me to do. I’ve been able to do that for periods of a couple of weeks, or a month, here and there over the last two years. My wife does the same thing. If she goes to the gym often enough, it becomes something she has to do. We’ve often done that together. We need to do that again.

The other thing I might need is a walk in the Kalahari with Lynne, or something similar, to act as motivation. Perhaps my brother’s recent major open heart surgery can inspire me. He went under the knife a few weeks ago. I don’t know if more exercise would have been good for him or not. But generally speaking, more exercise is better than less exercise.

Second funny thing: BFF Stephanie and I were working in the free weight area of the Kimberly gym one evening. There were a lot of people there. Then these two meaty looking guys came in and tossed a big rubber thingie on a bench. One of the guys then proceeded to unpack the rubber thingie, and it was some kind of shirt or jacket, much like (yet different from) a wet suit. So Guy One starts to put the jacket thing on, and Guy Two is helping him, but it seems to be several sizes too small.

These two guys struggled and struggled and struggled to get this rubber shirt onto Guy One. The two of them were pulling on it, grunting, groaning, yanking, shoving, and generally working up a great sweat. Finally, the somewhat fattish but muscular upper torso of Guy One was totally encased in this suit so he could hardly move. Guy Two helped him lay down on his back on one of the benches, and he put a bar across the stand that was attached to the bench. He then proceeded to carry free weights over to the bar and slide them on. I don’t know how much weight he put on there, but it was a fairly large amount. Not more than I’d ever seen anyone lift, but more than most people can lift. Then Guy Two got into spotting position, and Guy One put his hands up to the bar and pushed it off the stand.

The bar bell with the massive weights on each end was suspended, wobbling a bit, over Guy One, who was wearing the rubber suit. Guy One dropped the weight fairly quickly to his chest, then pushed it all the way back up with a huge ejaculation of sound. Guy Two grabbed the bar and helped Guy One position it back onto the stand.

One rep.

Then, for the next ten minutes, Guy Two helped Guy One get the rubber shirt off. Grunt, groan, push, shove, pull, snap. Finally it came off. And they left.

Made me laugh.

Funny story three: This is not really a funny story, but rather, a bald faced exploitation of the fact that you are reading this for the purpose of me showing off.

This was the same day as the Adventure of the Rubber Shirted Man. I wanted to do a leg press at what was my maximum capacity at the time I had left the states to see if I could still do it. That was 800 pounds. There was a leg press machine very much like the one I used at the gym back home. So I started out by counting out 300 and loading that up on the machine. I tried that and it seemed a lot harder than I expected it to be, so I decided to not try for the 800. I put 200 more on the machine, to make it an even 500 (plus the unknown weight of the carriage, usually about 50 pounds).

I pressed the 500 about 12 times. It was very very hard, but I did it. Normally, I would do 500 pounds at 30 reps or more. So this was something of a disappointment.

Until I went to remove the weights from the machine. Something didn’t seem right. I realized I was holding a weight that was labeled with one number but seemed to be the wrong size.

It was then that I realized what I had done. I had just leg pressed 500 kilos. 1,100 pounds.

I had a couple of muscles hurting the next day. And a couple of years later, when NASA crashed that space ship because they messed up the units of measurement, I didn’t say much about it….

… continued

Stuck in the field without a gym for three weeks was going to be tough, but I worked out two ways to stay in shape. First, every time we were in a city with a gym, Lynne got me into the gym, and my field crew usually came along as well. Lynne knew all the gyms and all the people who worked in all the gyms, and generally had the ability to make things happen. This mainly occurred in the city of Kimberly … which actually has a very nice gym … but I also worked out in Pretoria and Stellenbosch.

But that would not be enough. I needed more.

Our field survey required that we have a truck and a trailer. So, I bought a complete dumb-bell set at a store in Pretoria and packed it into the trailer. When I purchased the set, I told the clerk that I did not need the full length bar, just the adjustable dumb-bell bars. He insisted that I take the large bar because I had paid for it. I said I really didn’t want it. He checked with the manager. I had to take it. I said no. He said yes. So I said OK, I’ll take it. Then when I packed up all the stuff I had bought at that store (which included a lot of field gear as well as the weights) I “accidently”left behind the large bar.

I assume it is still there.

Anyway, whenever we’s set up camp somewhere, I’d pull out the weights. Lynne accompanied us to most of our field sites, but was not there all the time, so she rarely used them. Rather, she ran whenever she had the chance. There were, variously, four or five other people with us, but only two Americans, a grad student from The U, and my BFF, Stephanie. They decided they wanted to get buff, so they used the weights as well. So, after a day of survey, we’d come back, have some food and drink, and then get down with the weights out in front of the cabin. We stayed most of the time in a tourist rest camp near the Kalahari. Tourists would walk by and openly stare at us as we took turns lifting, spotting each other, writing down our progress on gridded note paper.

This worked. Before going to South Africa, I did a series of calibration exercises to establish the strength and endurance level of various muscle groups. When I got back from South Africa, I was ahead of where I had left off in all areas. Lenora was impressed.

Funny things happened at the gym in Kimberly. I remember three in particular.

First funny thing: There was a series of machines laid out in a very logical fashion, organized anatomically in the order one may well want to do a set of exercises. Thinking this rather convenient, I did an exercise on the first machine, a leg press of some kind, then moved on to the second machine, a leg lift. While I was using the leg lift, doing a few sets, a woman came over and waited for me to finish. I wasn’t sure why she needed to use this machine because there were other similar machines, but I did not think about it too much. When I fished the machine, she jumped on it like a Texas ranger on his horse.

So I moved on to the next machine, working hamstrings. While I worked, I noticed these funny lights, like traffic lights, up near the ceiling. They’d go from green to yellow then back to green in a cycle for several seconds. As I was wondering what those lights were for, that same woman, was suddenly there waiting for me to finish again. The next machine was calves, but I didn’t like that particular machine so I skipped it and moved on to a bench press kind of machine. I was using that machine when I noticed the woman who had been following me was using the calf machine. I then moved on to a back machine of some kind, as the woman moved to the machine I had just been on. She finished there and came over to me while I was still working my back, and started at me until I was done. Then she took over the back machine as I moved to the next machine, feeling this was all kind of strange, and stared working my abs.

I decided to really hit my abs because this particular bench thingie I was using was working really well. So I did a bunch of reps, rested, and did a bunch more, then adjusted the machine to make it harder, then did a bunch more, and then I was resting again when I noticed the woman was standing next to me, looking down at me, ready to say something.

So I gave hear a look like “Huh?” and she said, “What are you, a moron????” And I was like “Huh?” and she said “Do you not know that this is a circuit?” and I was like “Huh?” and she pointed to the traffic light thingie and gave me a really dirty look.

Suddenly I realized that these machines laid out in this order constituted what is called a “circuit” which is a series of machines laid out in a certain order with a timer attached to a flashing light of some kind. You were to move from one machine to the next as the light flashed. Like a trainer telling you to keep moving and work harder. A dumb robotic trainer attached to the ceiling.

So I looked at the woman and said “Well, that traffic light of yours is certainly no Lenora!” and she was like “Huh?” and I got the hell out of her way.

Oh, I see I have run out of time. I’ll tell you the other two stories next time.

Continued …

I got my six free sessions, and then I paid for a lot more. In the end, I’ve paid less for cars I’ve driven for years, but it was worth it. Having never been part of the “workout” culture, having never gone to a gym before, I found Lenora’s training to be invaluable.

We were efficient. I would arrive at the gym way before hand and do all my warm-ups. I’d do my post-workout stretches after the session, as well as selected exercises that Lenora would specify … but she never left any category of exercise entirely to me. There are certain exercises one should do last in a weight training session, so Lenora would schedule the occasional session to focus on just those particular things rather than letting me only do them on my own.

Lenora was relentless. She knew that no matter what I did, as long as I did it correctly, I would probably not die or injure myself. So she had no compunction whatsoever of pushing me beyond what I thought I could do. With every exercise. Every. Exercise. She timed how many seconds I had to rest between sets. She calculated things out so we would never have to wait between machines or free weights. She warned people off of equipment that we were about to use. She came up with diabolical plans whereby I would get absolutely no rest at all for long periods of time as I moved from muscle to muscle.

I learned about isolating muscles and why it was good to do that. Related to this, I learned why a lot of guys and some gals at the gym have back braces, and I learned how to not do that. I learned about breakdown, giant sets, super sets. I learned about pain. Good pain.

Over a period of a few months, my body weight did not go down more than a few pounds, but my muscle mass went way way up. My relative body fat dropped to an acceptable level (as measured using a couple of different techniques). I became big and strong. I was able to leg press 800 pounds. I’d always been fairly fit, able to walk great distances, dig deep holes, all that sort of thing. But now I could lift larger objects and move heavier things as well. I walked around town waiting for some poor sap to get trapped under a car so I could lift the car off him.

But then it was time to return to South Africa. After seven months of intense work, I was pretty much obsessed with working out, which is how one has to do this, really. I was worried that three months in the field would set me back. Never mind that field work itself is exercise. I did not believe that I would be able to maintain my condition from just field survey and a lot of driving.

So, I needed a plan for how to stay in shape while I was away. For several sessions, Lenora trained me in gym-free exercises, which helped. But I knew that would not be enough. To really stay in shape in the field, I’d have to do something drastic.

So, I did something drastic. …. (Continued)

By this time it had become clear that I was joining this gym with a life membership. I’d lay out a few hundred bucks and be a member for about $50 a year forever after. That may seem like a lot and these sorts of things are not always good deals. But part of my motivation for choosing the super-membership was to put the money down up front so I would be motivated to stick with the program for a long time. In the end, that worked.

As part of the deal, I got six hours of trainer time. I knew from my reading that working with a personal trainer was a good idea if you don’t know what you are doing, and I didn’t know what I was doing. A good personal trainer could save you from injuring yourself, and help you to be more effective in your training. I’ll tell you about some of the things I learned about this in a later post.

Lenora was one of the personal trainers at this gym, and it eventually became clear to me that the sales rep and head trainer with whom I’d met when I joined up figured out that I wanted to work with a serious personal trainer, and so they matched us up. And I’ll tell you this, since that time I’ve watched a lot of trainers working with various clients, and there is a great deal of variation across trainers, and across trainer-client relationships. There are people throwing away their money, and there are people who are getting a very, very valuable service.

I was determined to be in the latter group, and as a trainer, Lenora was determined to be in that group as well.

Lenora is medium to tall in height, and thin like a stick. She has soft brown eyes and a pleasant countenance, a quiet conversational voice and a very polite manner. When we first met she was very formal in her introduction, and after a few pleasantries and technicalities, she came to the key question.

“How hard do you want me to make you work.”

“Well, harder than anyone else you’ve ever worked with.”

A pause.

“Are you sure?”

“Well, I figure that if I don’t work hard enough to puke at least once every few sessions, we’re not working hard enough.”

She looked at me for a moment, trying to read how serious I was being. Then, just as she turned away to lead me to the evaluation area, she said, “Very well. We can do that.”

She may not have realized that I could see the grin appear across her face in the mirror towards which we were walking. Within three weeks I was to throw up once, and I was to collapse on the floor once. And those were the only times I was to see her grin in just that way again.

… CONTINUED……..

Back from South Africa and with some time on my hands, I was hell bent on keeping the promise I had made to myself to get back into shape. For most people I know, this would mean eating better and going to the gym more often. But for me, it meant eating better and going to a gym for the first time in my life.

I went to an elementary school with no athletic program. In Junior high, there was a minimal program but the other students I hung out with and I had figured out how to skip gym. Always. I did not attend high school. I did not attend college. I never joined a gym prior to the fateful Kalahari excursion with Lynne.

When I did eventually join a gym, and I’m going to tell you that story in a moment, I was an adult in my 30s, and the first time I went into the men’s locker room I saw more naked men all at once than I had seen in my entire life previously. That was also the first time I smelled a real gym locker room. Talk about sensory overload.

So, I went to a gym not too far from my house, and told them I wanted to join. This led to a meeting in an office with a couple of guys: a sales rep and a trainer. I had no idea that joining a gym would involve a committee meeting, but what the heck. The two men asked me a number of questions that I did not expect. They wanted to know why I wanted to join the gym. What were my objectives. At first I didn’t really have an answer for them, so they kept talking about why one might want to join a gym, a bit about their own personal experiences, and so on. They kept mentioning Thailand. I began to think that there was a connection between the Southeast Asian Sex Industry and joining a gym. Or maybe it was just these guys. I was confused.

Now, I should mention that as a biological anthropologist I was not totally ignorant of some of the fundamentals of diet and exercise, at least at the theoretical level, and before joining this gym, in the first two days after returning from South Africa, I had purchased and devoured a couple of fitness books. (In case you are interested, the most useful book I read was the then current version of Covert Bailey’s The Ultimate Fit or Fat) The point being, I did have some idea of what I was doing there, I had just not articulated it yet. But while these guys were talking about Thailand and other stuff, I formulated the answer I should have given them when I first walked in. SO I interrupted their conversation and told them.

“I know why I’m here.”

“Huh? Wha… Oh, OK, why are you here?”

“I want to be the kind of person who sits down in a public restaurant and orders three pieces of pie, and while I’m eating the pie other people in the restaurant look over and say to each other, ‘Wow. Look at that guy. How does he eat that way and stay so trim and fit?'”

They looked at each other. They laughed. They looked back at me. I was not laughing.

Then one of them said, “Let me introduce you to Lenora.”

… Continued. …

And as the cattle do, so do Scienceblogs.com bloggers. And the current stampede about to form up is about fitness. I’m not sure where it started, but I first noticed it at ERV‘s blog, but Page 3.14 has also picked it up.

We’re not talking about Darwinian fitness, but rather, physical fitness.

So, because I’m as much a member of the herd as the next cow, I decided to join in and tell you my fitness story … or at least, a version of it. Part I is below the fold.

Africa. Some time in the early 1990s.

I started out walking a good six feet behind her, to avoid the sand she was kicking up and the occasional thorn-lined branch that might swing behind anyone walking through the African Bush. We were traversing, extra-legally, an area people were not allowed because of the dangerous wild animals (mainly lion) and the chance of getting lost on this difficult to navigate terrain. We crossed the parallel linear dunes at a right angle …. up a grass covered dune, across it’s narrow top of red sand, down the next side, then across the bushy flat to the next dune. The reststation we were staying in, along with a dozen American travelers distributed among eight or nine grass-roofed chalets, was surrounded by a series of fences, the largest and outermost one being a 15 foot high affair designed to keep lions out and tourists in. Earlier in the day, I followed some of the camp workers to see where they got through the first fence, to the village they lived in. Then, using this intelligence, Lynne and I passed through that unlocked gate, and Lynne talked our way past a couple of security guards at other gates, then we found what was probably an informal smuggler’s opening in the 15 footer, and we were free.

Free in the Kalahari.

By now I was a full 20 or 30 feet behind Lynne, way more than necessary to avoid snapping branches. I decided to catch up a little just as we were about to mount the next dune, a bit larger than the last few. But Lynne took that moment to sprint rather than walk to the top, so while I also sprinted, I did not close the gap. In fact, she was down the other side of the dune before I attained the crest, and it took me a bit of work to get within 50 feet of her.

I hadn’t known Lynne very long, but we had been traveling together now for several days, and for reasons far beyond what I can explain here we had bonded rather quickly. Let’s just say diversity makes fast friends, and when there are only two of you in the lifeboat, you either sink or learn to trust each other. I was probably thinking about that, or about the strange holes we kept passing on the lower dune slopes that we later discovered to be silk spider traps, or the bright blue sky and the pleasant afternoon winter warmth when I noticed that Lynne had been out of my sight for a long time.

Finally, a few dunes later, I saw her at the bottom sitting in the shade of a Shepard’s tree. Eventually, I arrived at her rest spot, and we relaxed a bit and talked.

This is when I learned, while trying to catch my breath and not look too exhausted, that Lynne was considering herself to be rather out of shape. She told me that this trip was killing her. She needed to spend some time at the gym, she said, and this walk was telling her that she needed to do it soon. You see, Lynne was supposed to be in training for her first Ultra Marathon, a 250 kilometer race across the Green Kalahari. She had already run a couple of 50 km races that year as part of her prep, and she had also won a regional Ultimate Frisbee tournament and that was good, but with the race coming up soon she needed to be running every day and working with weights at least a few times a week. Neither was possible while we were guiding these tourists, staying mostly in game parks where we were not allowed to wander freely in the bush, and where there were no gyms.

So now I understood why Lynne was so keen on breaking out of the Kalahari restcamp, and I was glad we had done it. But I also realized, as I sat in the shade admiring my new friend’s stamina and resolve, that I had gone from a person who was always in pretty good shape to a person who was in the process of serious deterioration.

When I was a kid, I walked all the time. My parents were forever leaving me in various forests or on the side of lonely mountain roads, and I would always make my way home eventually, on foot. When I was a teenager, I had a girlfriend who lived far away, and a couple of five or six mile walks a day was a virtually daily thing for me (I did not grow up in a car culture). At that time, I would also spend a couple of weeks a year in the Adirondack mountains. I would cover between 90 and 150 miles, much of it over peaks reaching beyond 5,000 feet, often trail-less. Later, as an archaeologist, I walked and walked and walked, but often carrying piles of equipment and digging dozens and dozens of holes per day, on survey. Eventually, I went off to the Congo for fieldwork. I was famous among the pygmies for my walking there. I would routinely walk 10 miles through the forest one way with an empty pack, then 10 miles the other way with 110 pounds of food, or along the “road” either 10 or 20 miles, depending, to and from market.

I was always the one who was not tired, no matter how far we went or how much I carried.

Then it came time to write my thesis and do some other stuff, so I spent a few years mostly at a desk job and slowly slowly, month after month, my legendary walking muscles turned into something other than muscle, and though I had no more visible body fat than I had ever had I’m sure my muscle had all gone south.

And I knew this because as I sat under the Shepard’s tree, I realized that for the first time in my life, ever, I had been out-walked by another human being. Never mind that she was a semi-professional athlete marathon runner training for an ultra (which, by the way, she would indeed run, and in fact win, several times over the coming years).

So I resolved.

I resolved that on my return to the states, I would get my self in shape. And I did. I got myself very much in shape, and the next time I returned to South Africa, Lynne did not out walk me. And the next time after that, people at the gyms across South Africa found themselves in awe of my physical prowess as I traveled from place to place being … really really fit.

How did I do it? Well, I found Lenora, Inflicter of Pain. And I let her have her way with me. I’ll tell you about Lenora in the next installment.

…. continued ….