Thinking about paleo, with bonus anecdote

I have been on-and-off reading about “paleo” diet and exercise programs (also called “primal”).

I think there’s a lot to paleo, on an evolutionary basis. On the other hand, there are an awful lot of post-paleo lifestyles that have proven to be entirely successful, in the sense that generations of people have eaten all manner of particular diets and been healthy. (Native Americans ate corn, beans, and squash. Scots ate oats and kale. Lots of people ate rice and lentils.) Given that, and the fact that paleo diet programs doesn’t match well with what I like to eat, I’ve only paid a bit of attention to them. Basically, I’ve let them reinforce my preconceived notions.

I have a similarly divided appreciation of paleo exercise programs, but there I think I’ve worked out what was bugging me.

The half I agreed with is that very short bursts of very intense activity should be a key part of an exercise program. I’ve only made limited moves to incorporate this insight into my own workouts, but only because those sorts of intense bursts are hard.

I suspect it would be a really good change to compress my current 20-minute lifting workout into 10 minutes, which I could do if I really hustled between machines and counted the first set of the three leg exercises that I do as a warm-up.

To do so would require some additional mental toughness. It’s really hard to jump off the leg extension machine with your quads burning, and then jump on the leg curl machine and make your hamstrings feel the same way, and then hurry on to the leg press. Taking an extra thirty or forty seconds between machines to recover is a lot easier. (Not to mention inevitable, if you’re working out in a fitness center where you have to adjust the seat and set the weights on each machine.)

The half I disagreed with is the half that seems to dismiss endurance exercise.

Now, it may be that my reading of paleo exercise programs has simply been so cursory that I missed the paleo version of endurance exercise. But it sure seems to me like a large fraction of the paleo folks don’t merely dismiss endurance exercise, they actively disdain it.

That puzzled me, because it seems to me that the paleo human was the quintessential endurance machine.

As I say, I think I’ve come to understand the objection, which is that you can’t do high-intensity endurance exercise unless you eat loads of carbs. The paleo folks think you should do endurance exercise, as long as you keep the intensity level at a level where you can perform on a low-carb diet. Further, they seem to think that the appropriate level supports walking or hiking, but doesn’t support endurance running.

That’s crazy, although it’s understandable. The modern way of training to run is all about prompting the body to mobilize glycogen stores, by depleting those stores and then eating a high-carb diet to replenish and boost them.

That is not the only way to run. You can also engage in endurance activity powered mainly by fat stores.

Begin bonus anecdote:

When I was in high school, I decided to bicycle to Saugatuck, see a play, camp out overnight, and ride home the next day. I didn’t have a cyclometer in those days, and have always claimed that the distance was 75 miles each way. Google Maps tells me that my route (or very close to it) is 69.3 miles. Close enough.

I knew nothing about carb or fat metabolism. I made no plans to get food along the way, and in fact ate very little.

I headed out early in the morning, did just fine for a bit more than the 36 mile I was used to riding, and then bonked at about mile 40. (Bonking is what cyclists call it when you exhaust your body’s glycogen stores. It’s the same thing marathoners call “hitting the wall.”)

I was exhausted. My speed dropped from 14–17 mph down to 7–8 mph. And it stayed there.

That’s the important part of this anecdote. It stayed there. I rode another 30 miles or so that way. I rode it at less than 8 mph, but I rode it. I got up the next morning, still exhausted, got back on my bike, and rode a few miles to a breakfast spot and ate my only proper meal of the whole trip. It didn’t help much. I rode the whole way home at 7–8 mph.

End bonus anecdote.

If you haven’t trained your body to use fat stores for endurance activity, you’ll be pretty slow—as I was on my ride. And you’ll never be fast the way someone who has trained to build up glycogen stores can be. But with a modest amount of training, you can be plenty fast enough to run.

There are times when it is convenient to be able to run for an extended period. If you want to have that capability, you need to run—and not just occasional short sprints during your walks.

We don’t have much direct evidence of what paleolithic humans actually did, but I have no doubt that, in addition to walking a lot, they ran a lot. The human body is just too well adapted for long-distance running for it not to have been a key capability over an evolutionarily long period.

An open-ended run

Yesterday, I went on my first open-ended run of the season.

On earlier runs, I pretty much knew how far I was going to go and what route I’d follow. Occasionally there’d be a bit of room for variation—I might think, “If I’m feeling good, maybe I’ll add a second lap around Kaufman Lake,” or “Maybe I’ll add the leg out to Bradley and back.” But by and large, I knew to within a few tenths of a mile how far I’d run before I took my first step.

The reason was that every run would take me a large fraction of as far as I could run. There was no chance I’d just decide on a whim to go a few miles further, because I couldn’t run a few miles further.

So, it was a great treat yesterday, to head out for a run with only a general idea of where I’d be running, and with no specific plan how far I’d go.

I knew I’d run halfway down O’Malley’s Alley (the short bit of rail trail that I call McNalley’s Alley), and then cut over into the neighborhood south of there. But I’d had only a vague, somewhat aspirational notion that I’d continue on as far as the trail through Robeson Park. But I knew that the trail would cross several different roads, and that I’d be able to head for home on any one of them, if I decided that I’d run as far as made sense.

In the end, I headed home when I got to Crescent. On some future run, I’ll push on as far as Mattis, and maybe continue on down the Simon trail before heading home.

This run, according to my GPS thingy, came to 4.84 miles, which I ran in 54:15, for an average pace of a bit over 11 minutes per mile. And it was a great run. My feet didn’t hurt, nor did my ankles, knees, hips, or any other bits. I did get pretty tired by the end, but not over-tired. In fact, after a bit of a rest and rehydration, I had enough energy to bicycle 9 miles, lift weights, and do an hour of taiji. (The lifting, I must admit, was a rather feeble effort.)

At over 50 minutes, it was definitely a long-enough endurance effort to produce significant levels of endocannabinoids, which I presume is the reason that my memory of the run is mainly just a strong sense that I was having fun and feeling good. There are only a few spots where specific details are sharp and clear—the spot where I had to back up and run on the grass next to the trail, to avoid a muddy patch, the spot where I thought, “There’s a hill here? How did I not know there was a hill here?” and the spot where I slowed to a walk so I could look back over my shoulder and read a street sign, so I’d be able to make a map.

Speaking of which, here’s a map of the run:

Reportedly in great shape for my age

My run on Monday included two laps around Kaufman Lake. Among the people that I encountered more than once was a pair of young black men. I don’t know how old they were—in their twenties, I suppose.

As I passed them the second time, one of them asked how old I was. I told him I was 52. He said, “Wow! You’re in great shape!” I thanked him and ran on.

That brief conversation has stuck with me.

First of all, I don’t think of myself as being in great shape, although I’m getting fitter. That particular run went on to be 2.4 miles at an 11:27 pace. That matches the distance of my longest previous run this year, and was actually the best pace I’d managed at any distance in a very long time. (When I’m estimating time or distance, I generally assume a 12-minute pace.)

Jackie pointed out that, if I was right about the men’s ages, their fathers would probably be just about my age. That might well mean that they have a very specific referent for the default fitness level of a man in his 50s.

There are certainly a lot of men in their 50s that are in pretty poor shape, but that doesn’t mean that I’m in good shape, let alone great shape. I’m still quite overweight (although as of a couple of weeks ago, no longer obese, according to the National Institutes of Health). I’m not in nearly as good shape as I was in 2004, when I was routinely running 6 and 7 miles for my long runs, nor the summer of 2005 when I was working my way up to riding a 100-mile bike ride.

Today’s run was 1.5 miles at an 11:22 pace. I’ve been recording my 1.5 mile runs as “easy” runs in my training log, but this was really the first one this year that qualified. The previous ones, if judged objectively (by heart rate, etc.) would rightly have been classified as “hard” runs. But I’m past that stage. I can run along at a comfortable lope and not be maxing out my aerobic capacity.

This is when running gets fun. And maybe that is the same thing as being in great shape.

Daily routine of Vestricius Spurinna

I’m a student of daily routines. I like to imagine that I’m looking for good models for my own behavior, but that’s only true in an oblique way. By now I understand pretty well the structure of a productive routine; no new routine will be enough better than the routines I’ve already studied to justify the effort of examining them. The value in studying daily routines, for me, is as a reminder to follow my own routine.

For a while there was a great blog called Daily Routines that was very nearly pornography for this inclination of mine to ponder new models. It was there that I found the daily routine for Charles Darwin, which is probably the best model I’ve found so far.

And it is in part because of its similarity to Darwin’s model, that the daily routine of Vestricius Spurinna caught my eye:

At the second hour [after waking] he calls for his shoes and walks three miles, exercising mind as well as body. If he has friends with him the time is passed in conversation on the noblest of themes, otherwise a book is read aloud….

Then he sits down, and there is more reading aloud or more talk for preference; afterwards he enters his carriage [for more private conversation].

After riding seven miles he walks another mile, then he again resumes his seat or betakes himself to his room and his pen. For he composes, both in Latin and Greek, the most scholarly lyrics. They have a wonderful grace, wonderful sweetness, and wonderful humour, and the chastity of the writer enhances its charm.

When he is told that the bathing hour has come—which is the ninth hour in winter and the eighth in summer—he takes a walk naked in the sun, if there is no wind.

Then he plays at ball for a long spell, throwing himself heartily into the game, for it is by means of this kind of active exercise that he battles with old age.

After his bath he lies down and waits a little while before taking food, listening in the meantime to the reading of some light and pleasant book. All this time his friends are at perfect liberty to imitate his example or do anything else they prefer.

Then dinner is served…. The dinner is often relieved by actors of comedy, so that the pleasures of the table may have a seasoning of letters. Even in the summer the meal lasts well into the night, but no one finds it long, for it is kept up with such good humour and charm.

The consequence is that, though he has passed his seventy-seventh year, his hearing and eyesight are as good as ever, his body is still active and alert, and the only symptom of his age is his wisdom.

– (From a public-domain translation of the letters of Pliny the Younger.)

Of course, Spurinna was retired, so one writing session of just an hour or two is probably enough for him. His work when he was younger was as a magistrate and governor, and so probably took place in those conversation sessions that are now just for pleasure.

I think there’s a lot to emulate there. Three walks per day adding up to five miles seems just about right—as long as you include another hour or two of vigorous sport. Of course, he’s in his late seventies. Us younger folk should probably get in a little more than that.

More on endocannabinoids

Last month I posted a bit on endocannabinoid production in cursorial mammals, pointing to an article on new research that both supports the hypothesis that endocannabinoids are responsible for runners high, and that the whole system may have evolved to encourage and facilitate long-distance running in mammals whose success depends on it.

I found that I was still quite interested in endocannabinoids and running, and a little more research brought me to this 2004 survey paper by A Dietrich and W F McDaniel in the British Journal of Sports Medicine, endocannabinoids and exercise. It turns out endocannabinoids are involved in a whole range of systems, both centrally in the brain and peripherally in the rest of the body.

Some of the things that endocannabinoids do are entirely to be expected by anyone who has any experience with exogenous cannabinoids: pain relief, sedation, reduced anxiety, euphoria, and a general sense of wellbeing.

But other things were new to me:

  • Anandamide, a particular endocannabinoid, prevents edema and inflammation—probably a very useful mechanism. After all, running is bound to produce minor tissue damage to the feet and legs. Those endocannabinoids probably greatly reduce the need to get clever with ice and elevation and compression and anti-inflammatory drugs.
  • Anadamide also acts as a vasodilator and produces hypotension, perhaps facilitating blood flow during exercise.
  • Although in large doses cannabinoids produce motor inhibition, in low doses they produce increased locomotion. It appears that they make it easier to perform motor skills that have been practiced to the point where performance is automatic, such as running.
  • Cannabinoids act as brochodilators, perhaps facilitating breathing during exercise.

On that last point, I’ve certainly noticed that going for a run produces a profound relaxation of my upper airways. My nasal passages are pretty much permanently inflamed due to allergies—to the point that I spent most of last year needing to use a nasal steroid spray if I wanted to be able to breath through my nose. I have no idea if it’s mediated by endocannabinoids, but my nose is much, much more open after a run than it is before a run, and the effect lasts for hours.

One thing I found particularly interesting was an explanation for why cannabinoids don’t seem to be very addictive. They’re involved in the same dopamine systems that other addictive drugs are, and by rights ought to produce withdrawal symptoms when they’re withdrawn. In fact, you can produce those symptoms (in rats), by habituating the rats to THC and then administering an antagonist that blocks cannabinoid receptors. But mere withdrawal of the drug won’t do it, apparently because the drug hangs around in the system for so long that even abrupt withdrawal ends up resulting in a gradual tapering off.

On the other hand, gradual withdrawal is still withdrawal—even if it’s not drastic enough to produce shakes—and endocannabinoids may explain not only runners high, but also the addictive behaviors reported in runners:

We do not suggest that the addictive aspects of exercise are identical with the addictive properties of exogenous cannabinoids, but that a similarity exists between the desire that some people have for exercise and the desire they may have for exogenous administrations of cannabinoids. The parallels between these results and the subjective experiences associated with exercise abstinence, as discussed previously, are considerable.

What led me to this paper in the first place was a desire to get some data on just how much exercise was necessary to start producing endocannabinoids. On that question, the paper does provide a datapoint:

Using trained male college students running on a treadmill or cycling on a stationary bike for 50 minutes at 70–80% of maximum heart rate, we found that exercise of moderate intensity dramatically increased concentrations of anandamide in blood plasma.

That sounds pretty reasonable, although I wish they had data for exercise for 10 to 40 minutes as well. My guess, based on reports of runners high, is that it does take upwards of 50 minutes to start seeing a significant increase, but it’s just a guess. It’d be nice to have some data.

Most unconditioned people can’t maintain 70–80% of maximum heart rate for 50 minutes, meaning that if it’s true that it takes 50 minutes, most people won’t be able to experience this “dramatic” increase. The typical sedentary person would probably have to train for weeks to achieve this level of performance.

So far this year, my longest run was 26 minutes. But it was a great run (unlike my first long runs of the previous two years, which were not entirely successful). I’m quite optimistic that I’ll be able to ramp up the distance without much difficulty.

The wrong class of euphoria-inducing chemicals

Chuck McCaffery and me, after finishing the Allerton Park Trail Race in 2003
Chuck McCaffery and me, after finishing the 5.5 mile Allerton Park Trail Race in 2003. Photo by Jackie Brewer.

I remember back in the late 1970s and early 1980s people were speculating that endorphins might be the source of runners high—and I remember how disappointed they were when experiments showed that exercise-induced levels of endorphins were much too low to produce the reported levels of euphoria.

They may simply have been looking for the wrong class of euphoria-inducing chemicals—it now looks like runners high may be produced not by endorphins but by endocannabinoids. Further, according to a paper in the Journal of Experimental Biology, there’s reason to believe that this euphoria is important enough in improving reproductive fitness that it is broadly selected for in cursorial mammals (that is, those with bodies suited for running). See Endocannabinoids motivated exercise evolution for an overview. (The paper itself is behind an annoying paywall for people without some sort of university affiliation.)

This could explain a lot of otherwise hard-to-explain behavior:

. . . a neurobiological reward for endurance exercise may explain why humans and other cursorial mammals habitually engage in aerobic exercise despite the higher associated energy costs and injury risks, and why non-cursorial mammals avoid such locomotor behaviors.

Sadly, the evolved system does not show much promise for turning couch potatoes into endurance athletes:

. . . couch potatoes are not about to leap suddenly out of their comfy chairs and experience the pleasurable effects of exercise, because they probably cannot produce enough endocannabinoids. . . . Inactive people may not be fit enough to hit the exercise intensity that leads to this sort of rewarding sensation.

This is why I’m so pleased at having come up with an exercise regimen that I can persist with over the winter—I enter spring already able to enjoy the euphoric joys of exercise without having to first get in shape.

Local taiji blog

The local taiji group that I practice with, Community Tai Chi, recently opened up its formerly closed (password protected) Community Tai Chi student blog.

If you’re local, and you’re interested in studying taiji, the site and the blog together give you a very good idea of what you’d be studying if you studied with us. At the top of the blog are a series of posts with links to videos of the various movements in the 8-movement form we teach beginners (reposted so that they appear in order). Further down is a long post with links to videos of the 24-movement form that the more advanced class is working on (the first 24 of the Chen-style 48 movement form). Further down yet are some older posts with links to taiji resources various other places (including a couple that link back here, to some of my taiji posts).

Running and me

I’m of two minds about running for exercise. Except when I’m running or wishing I was running; then I’m all for it.

I used to have a lot of reasons I ran for exercise, but they’ve been dropping away.

One reason that I run for exercise is that I want to be able to run. (Sometimes I want to get somewhere reasonably close in a hurry, and running is great for that.) I always figured that, if I wanted to be able to run, I needed to run for exercise—to build and maintain the capability.

Except, twice this month I had to run to catch the bus, and I did—even though I haven’t been running for exercise since last year. These impromptu bus-catching runs weren’t long runs, but I did them flat-out, without warmup or stretching, wearing whatever shoes I had on at the time—and both times were fine. I did them without undue effort and without getting hurt.

So, it seems that my regular fitness activities are enough to maintain at least a minimum capability for running.

Another reason I run for exercise is that it’s wonderfully efficient. All winter, the aerobic portion of my fitness regimen has been to walk for an hour on the four days a week that I’m not lifting and doing taiji. In an hour I walk a bit over 3 miles. If I cover the same distance running, I do it a good bit more quickly, meaning that I don’t have to spend as much of the day exercising.

Except that I’ve found myself fitting the hour of walking in very easily, without scheduling any exercise at all. There are several local errands (grocery store, bank, neighborhood restaurants) that are about a 10 minute walk each way. To run my slightly more distant errands, I take the bus. It’s a similar 10 minute walk to the bus stop, but that’s typically followed by 10 minutes of walking at the other end as well, for a total of 20 minutes walking each way.

So, if I go on one outing by bus plus one neighborhood errand, that’s my 60 minutes already. Running is efficient, but it’s not more efficient than that.

Less important than either of those, but still a reason I run, is that it gives me a sense of health and fitness. If I have an irrational sense that there’s something wrong with me, going for a run will usually take care of it. (Surely, I tell myself, if there were something really wrong with me, I wouldn’t be able to run like this.) I always knew that this was the sort of false comfort that’s only appropriate when I’m really quite sure that my sense of unwellness is, in fact, irrational. Going for a run is a fine way of dealing with, let’s say, a  panic attack. It’s a really dumb way to deal with a heart attack. (I don’t have panic attacks, but I am prone to worrying about my health unnecessarily. Those worries don’t prey on my mind as much when I’m running regularly.)

The problem with running is that I get hurt. Almost every runner I know gets hurt. To the best of my recollection, I’ve never had a walking injury more serious than a blister nor a bicycling injury more serious than a sore butt. But I’ve lost months of exercise time due to running injuries.

Still, despite the problems with running, and despite the loss of some of my rationalizations for running, I’ve started running again. But I’m doing it a little differently, now that I recognize that my reasons for running aren’t as strong as I’d thought they were.

Now I recognize that I run mainly for fun. I run because I really enjoy it. I enjoy the runs themselves. I enjoy the feeling of tiredness in my legs after a run. I enjoy knowing that I can run further and faster than I’m likely to need to.

If my enjoyment is the main reason I do it, that suggests that I should only do the fun part. So, I’ll abandon any effort to make a plan or set a schedule. I used to carefully structure my runs around an idea of stress followed by recovery. (I’ll still include both stress and recovery, but I’ll just decide each day which is appropriate, based on how I feel.) I used to aim to be able to run a particular distance on a particular date, so I could run in a race. I won’t do that any more. (Although I might run a race on a whim, if I feel like it.)

I went on my second run of the year today. It felt great. My first run, a couple of days ago—merely a good run—moved me to haiku. In the original Esperanto, it’s:

spiro laboras, genuoj doloretas… jara ekkuro.

Which in English might be rendered as:

Breathing hard,
Knees a little tender…
Year’s first run.

The birds think it’s spring

Jackie and I went for our first bike ride of the year. We followed our traditional first-ride route, around Kaufman Lake, past the Olympic Monument, around Parkland College, and then back. This year we went 6.27 miles.

I’d been hearing cardinals for several days, but out on this ride we got definitive expressions of bird spring. The robins are back, as are the red-winged blackbirds. I saw a crow fly up out of Copper Slough with a huge wad of nesting material in its beak.

The ride itself went fine as well. No mechanical problems. No problems with Jackie’s wrist. There had been a couple of previous days when it would have been warm enough to ride, but those days were very windy. It was nice to just wait for today and not have to deal with the headwinds.

I think we’re all set now, to be able to ride whenever we want. In particular, if there’s a day when it’s nice enough to ride first thing in the morning, we could ride to the Fitness Center and then to taiji. (That’s a bit long and complex of a ride to try to combine it with our first “shakedown” ride of the year.)

Lifting: a personal experiment with multiple sets

I first started lifting at a gym that used Nautilus equipment, where the staff promoted a Nautilus-style system of doing one set to failure. (That is, where you pick a weight that you can lift at least 8 times, but that you can’t lift more than 12 times.)

I understood right from the start that the system’s big attraction is for the gym owner: If everybody just did one set, the gym could sell two or three times as many memberships. However, I also found the physiology compelling: lifting as much as you can, and then attempting to lift a little more, is a powerful signal to your muscles that they need to become stronger.

I’ve generally stuck with single-set-to-failure workouts, because I’m lazy and find lifting boring: I want to get my workouts over with as quickly as possible and get on to something else.

Just lately, I’ve been experimenting with multiple sets. The reason is that, in the winter, my knees aren’t warmed up enough to lift a weight heavy enough to produce muscle failure in just 12 reps. If I try to push a weight that heavy, my knees hurt.

So, I’ve rearranged my lower-body workout. I’m now doing a first set of leg extension, leg curl, and leg press with a weight about one notch lower than my target weight, and then do a second set of all three with my target weight.

It’s working great. The first set serves as an excellent warm-up for my knees, getting the synovial fluid warmed up and flowing. The second set works the muscles to failure without knee pain. (On the leg press, I often do a third short set with an even higher weight, but that’s probably just because I’ve long been using too low of a weight, because it was all my knees could handle without a better warm-up.)

It’s working so well, I’m inclined to experiment with multiple sets for my upper body as well. I’m not sure it’s really a parallel situation, because I don’t have a joint issue that’s keeping me from reaching muscle failure, but doing the heavy workout with properly warmed-up joints just feels better, aside from not hurting.