Weird (horrifying) study of human movement

A couple of weeks ago the New York Times linked to a new study on age-related declines in human movement. It’s an odd study, but not because of the result (which shows that children start moving less at age 6), because that seems entirely predictable to me, despite the general understanding previously having been that the decline started in adolescence.

Rather, what makes the study seem odd to me is the weird blind spot the researchers seem to have about when and how organisms (including humans) choose to move.

In the study itself the researchers make clear that they had considered the obvious presumption—that kids start moving less when they start going to school: “The overt explanation for this earlier decline could be the increased sitting times due to school.”

The  blind spot I’m talking about is presented in the next sentence, where they immediately qualified that:

However, time-specific analysis of [physical activity] has revealed that in addition to the increased [sedentary behavior] during school hours, there was also a distinct decline on weekends, out-of-school days, and during lunchtime.

Schwarzfischer P, Gruszfeld D, Stolarczyk A, et al. Physical Activity and Sedentary Behavior From 6 to 11 Years.Pediatrics. 2019;143(1):e20180994

What’s weird and horrifying is that they make that statement seemingly without it occurring to them that forcing children to sit still for hours on 5/7ths of the days of the week might affect their behavior on the other 2/7ths of the days.

Right off the top of my head I can think of four obvious reasons that would be true:

  1. The required behavior in school normalizes the behavior of extended sitting.
  2. Even a few weeks of enforced extended sitting will result in the kids becoming deconditioned aerobically, making physical activity more difficult and less appealing.
  3. Extended periods spent in any static posture—especially the static posture of sitting—will begin the process of reducing their range of motion (they’ll pretty quickly lose the ability to squat, for example), again making physical activity more difficult and less appealing.
  4. The addition of “physical education” to the kids daily schedule sets the pattern of replacing movement with exercise—a time-bound, regimented activity which attempts to pack the health benefits of a week’s worth of movement into just a few hours. (I’ve written about this before.)

Just one instance of this blind spot is bad enough, but it shows up again in in a key reference. The researchers say that it is accepted that physical activity declines with age: “A natural and biologically determined decline of total [physical activity] throughout the life span seems likely.” They support that assertion with a couple of references, one of which looks specifically at movement in non-human animals.

Unfortunately that study (Ingram, D. K. Age-related decline in physical activity: generalization to nonhumans. Med. Sci. Sports Exerc., Vol. 32, No. 9, pp. 1623-1629, 2000, which is sadly behind a pay-wall.) has exactly the same blind spot: All the animals studied were captive animals. That study looked at how animal movement varies when an animal is moved from its “home cage” to some other cage. I can’t say I’m the least bit surprised the behavior of those captive animals closely resembles the behavior of children moved from home to school and back again.

I would be very interested in studies that included some free-range animals. (Which isn’t something I can do, but which seems at least possible now that accelerometers  are cheap.)

Of course school isn’t the only factor that inhibits children from moving more. The restrictions on self-directed play so well documented by Lenore Skenazy of Let Grow no doubt feed in as well.

So it would be great if there were studies of movement in free-range kids as well.

The final weird and horrifying thing isn’t anything new, but is something I hadn’t really been aware of before: The assumption that an age-related reduction in movement is “natural and biologically determined,” has led directly to public policies that normalize it:

This decline is also represented in recommendations from the World Health Organization (WHO): preschool-aged children should accumulate a minimum of 180 minutes per day of total [physical activity], children and adolescents (4–17 years old) at least 60 minutes per day, and adults only a minimum of 30 minutes per day in moderate-to-vigorous physical activity (MVPA).

To which I say, “Argh!”

I probably wouldn’t be so struck by this if I weren’t already tracking my own movement. (Cheap accelerometers again.)

For some time now I’ve been working to a goal of 105 minutes of movement per day, and over the last few weeks I’ve come pretty close, averaging just over 102 minutes of movement per day, according to Google Fit. (This number, based primarily on steps, somewhat underestimates my movement. In particular it gives me almost no credit for the time I spend teaching taiji, because although there’s plenty of movement, there’s not much stepping.)

The WHO recommendations make me strongly motivated to upgrade my goal for movement to 180 minutes per day.

Why should kids under 6 get all the fun?

(The image at the top is topical only in that it is is a photo from our afternoon walk yesterday.)

Oura-ringing out the old year

For a couple of years now, I’ve been having some trouble sleeping. It’s not a constant problem, but it has become more frequent than the rare thing it used to be.

I think the problem is just a string of one-off instances of stress. During this period I had one older relative begin having cognitive difficulties and have to move to a facility that could provide additional care, my cat got sick and eventually died, had some personality clashes related to volunteer work I’m doing grow into a problem that eventually involved lawyers, and had another older relative began showing signs of cognitive difficulties.

Each of these resulted in a pattern where I’d fall asleep just fine, but then wake up in the middle of the night and start ruminating about the issue of the day and be unable to fall back to sleep for an hour or three.

In the past when I had problems of this sort they tended to be short-lived. I’d stress out about something for a night or two or three, but the issue would be resolved soon enough and I go back to sleeping fine.

Here the issues have stacked up, new ones following the old ones.  Further, some of them don’t go away. They linger on.

As I say, I think that’s what’s happening here. Ordinary life stresses have simply come at me a little too hard and a little too fast, with the result that my sleep has been impacted.

However, maybe that’s not all that’s going on. Maybe there’s more to it. I know there are some other issues. For example, if I don’t keep my carb intake down my nasal congestion returns, and that dramatically interferes with my sleep.

Given that I’m not sure what all might be wrong, I thought it might make sense to investigate further—gather some data, and see if I couldn’t find some patterns in my sleep problems. To that end, I bought an Oura ring, a tracking device along the lines of an Apple watch or a Fitbit, but with its focus specifically on gathering and analyzing data about sleep.

I’ve only had it for a week so far, and I’m really just getting started at looking for trends in the data. For example, three nights ago I slept poorly (awake for almost 2.5 hours of the almost 9 hours I was in bed).

One possible reason was a too-large meal too late in the day. (It was the Winfield Village holiday party.) One piece of data that suggests that possibility is that my body temperature was elevated by 0.3℃ during the night—perhaps because of increased metabolic activity digesting all that food.

Interestingly, I got more deep sleep than I had all week up to now, perhaps because I went for a long run the day before. (Deep sleep is where you get the physical recovery from things like heavy weight-lifting sessions and long runs. Maybe the first few nights had less deep sleep simply because I didn’t need more than that, because I hadn’t had the hard workouts that require deep sleep for recovery.)

Here’s the next night, where I spent less time awake and almost as much time in deep sleep:

My body temperature was still up, though, even without the big meal. We had turned the thermostat down one more degree, but that’s about as low as we want it, so last night I rearranged the covers, removing the down comforter, going with just the wool blanket. I don’t know if that was a key change, but I slept very well last night:

Not only were my quantities of total sleep and deep sleep good, some of the other metrics were good as well. My temperature deviation was -0.3℃, which suggests that maybe I’ve got the covers and thermostat thing balanced just about right. My resting heart rate was down to 47, which suggests that I’ve recovered completely from the long run I took three days ago.

My hope is that by paying attention to this sort of thing, I can gradually eliminate these sorts of problems affecting my sleep. Of course that will leave me with the stress-related problems, but I think I know how to handle those—fixing the ones that can be fixed, accepting the ones that can’t be fixed, and engaging in appropriate self-care to help myself handle the stress better. And, of course, get enough sleep.

Making things better with oil

There’s something—maybe just something cultural, maybe something embedded in the human genome—but something about the cold dark days of winter prompts me to want to preserve and protect things.

I have a wooden spoon that I use to stir up Bubbles, our sourdough starter. (Folk wisdom is to avoid using metal tools with a sourdough starter.) I’ve used this spoon for many years now, and after all those years the wood was getting a bit furred.

So last week I got out some sandpaper, sanded down the rough bits, and then treated the wood with oil. I did the same thing with the wooden cutting board we use for the bread loaves. 

With this task in mind, I got some flaxseed oil at the grocery store, with an eye toward it being a pretty finishing oil, as well as being food-safe.

I also have a leather jacket that I got more than 25 years ago when I was learning to ride a motorcycle, and that was similarly showing its age, and also needed a nice rubbing down with oil.

For the leather jacket I used neatsfoot oil. (It’s worth following that link. Neatsfoot oil is interesting stuff.) As long as I had the neatsfoot oil out, I went ahead and oiled a pair of leather boots too.

In all these cases I’m pleased with the results—I protected and preserved something, while also making it more beautiful. But more pleasing than the results, I think, was the process. Rubbing something with oil is a simple process, but one that rewards mindfulness in a way that makes it inherently meditative.

It makes caring for your stuff into a form of self-care, in the dark days of winter.

Workers skipping the stress and paperwork of resigning

Despite the unnecessary casting of aspersions on millennials in the setup to this piece, it’s both pretty good and pretty satisfying.

There are many things about looking for a job that suck, and the way potential employers treat you—beginning with running your resume through an opaque filter that decides whether you get an interview or not, and ending with simply never telling you that you didn’t get the job—is near the top of the list.

Given that, I have considerable sympathy with employees who find a better job taking the easy way out for quitting: just not showing up. (Frankly, I’m sure employers would totally do the same thing if there wasn’t a Department of Labor telling them that they had to pay you for any hours that you work after they secretly let you go.)

It would be very easy for employers to avoid this fate almost entirely. First, by treating their employees with respect, like people who matter as individuals. Second, by making sure that their employee’s interest align with the interests of the enterprise, though things like an equity interest and bonuses that depend on the success of the enterprise (rather than on stupid metrics that supposedly measure the employee’s performance).

“Employees leave jobs that suck,” they said in an email. “Jobs where they’re abused. Jobs where they don’t care about the work. And the less engaged they are, the less need they feel to give their bosses any warning.”

Source: Workers are ghosting their employers like bad dates – The Washington Post

Bone broth (or, as we call it, broth)

I have been amused to see “bone broth” trending of late, as I can’t remember the last time our household cooked anything with a bone in it and then failed to make broth out of it. It has been decades, at least.

(If something just has a bit of bone, like a serving of ribs or a bone-in steak or chop, we put the bone in the freezer and then throw it in with the next carcass we boil down for broth.)

Still, with broth showing up so much in the media lately, I keep wanting more of it (due merely to the power of suggestion), and although we eat plenty of meat, our roasting of carcasses hasn’t quite kept up with our broth needs.

So Thursday I swung by the butcher and got something over 4 pounds of frozen chicken necks. (They freeze them in a big trough-shaped container from which they can saw off a block of about three inches high by 4 inches deep by as long as someone wants.)

I put the block in a roasting pan and put it in the oven at 325℉ until it started being possible to pull off individual necks. Then I turned it up to 400℉ so I could get a bit of browning of the skin and pick up some nice roasty flavor. Once I had the necks a little bit roasted, I divided them between two big soup pots, added a little cider vinegar, a roughly quartered onion, some celery tops, and water. Then I boiled them for 3 or 4 hours, which wasn’t as long as would be ideal, but thawing the big block had taken longer than I’d expected and it was getting on to bedtime. Yield: about 12 cups of broth.

The butcher also sells cow femurs to use for broth, but that’s crazy. The good stuff in broth comes at least as much from the associated connective tissue as it does from the bones themselves. What you want is something like a tail or a back or a neck—something with lots of cartilage, ligaments, and tendons along with the bones. Skin is nice too.

Today I used three cups of my fresh broth and three cups of frozen broth from a recent smoked chicken carcass to make some lentil soup (with red lentils and red carrots, but foolishly not red onions or red potatoes, even though I had some of each).

It came out a little neutral in flavor—it had some dried red pepper as well, but turned out not to be as spicy as I’d expected. I added extra salt and black pepper and vinegar at the table, and it was yummy. I figure slightly neutral will be great for leftovers, as we can mix up the spices however we want.

Currently reading: Tea with the Black Dragon by R. A. Macavoy, ISBN: 9781497642294

Currently reading: Tea with the Black Dragon by R. A. Macavoy, ISBN: 9781497642294