Monday, November 28, 2016

Stuff I Learned - Week #14

This past week of school was significantly shortened by the Thanksgiving holiday. As a result, I learned about 60% less than most other weeks. Despite the paucity of class time, there was still plenty of work to do and stuff that I learned.

For this week's blog, I have been debating whether to write about basal ganglia or diabetes. Writing about basal ganglia would reference my neural control course, whereas writing about diabetes would refer to my exercise physiology course. For a couple of reasons, I've not written very much about my neural control course thus far this semester.

As far as coursework, neural control is more closely related to my research interests than exercise physiology. That being said, I've aways loved to move my body and work out. And the exercise physiology course has focused on what happens while moving the body and working out! I've found this exercise physiology course to be personally very interesting, and the material also potentially interesting to those that are fond of yoga and other physical activities.

As the name may imply, neural control can be pretty technical. By studying various neurological conditions such as Parkinson's disease, stroke, and deafferentation, our class has been learning about the various brain structures and neural circuits that underlie our sensing of the world and how we move through our world. Fascinating stuff!

Next semester I anticipate significantly deepening my understanding of neural control by being a teaching assistant (TA) for an undergraduate neural control course. I imagine that I'll come away from Spring semester with a much richer understanding of movement and its neural signaling. It's been said; if you really want to understand something, teach it!

Along with TA-ing neural control next semester, I'll also be taking a graduate-level neuroscience course, systems neuroscience. The systems neuroscience course has humbled people far more intelligent than me, so I'm girding myself for a busy semester of memorizing. While the price of admission to systems neuroscience seems to be a daunting amount of work, the payback promises to be incredibly rich - I've long desired a better understanding of the brain circuitry that underlies the richness of our lives.

You may be wondering, what does this have to do with basal ganglia or diabetes? Well, the short answer is that this blog posting, at least thus far, has had virtually nothing to do with either one! So, I'd best get to work - and write a bit about diabetes.

I took away three primary points from the recent lecture on T2DM (Type 2 Diabetes Mellitus). The first two points weren't really new information, but rather a clearer presentation on material that I'd heard before.

The primary causes of T2DM are lack of physical activity and obesity. There are certainly other factors at play in the increasing incidence of T2DM (such as familial history, ethnic predispositions, etc.), though being obese and sedentary overwhelmingly increases the risk of developing T2DM. I had heard this before, though it was a good reminder to keep moving and to avoid regaining the 40-pounds that I recently lost.

A point about diabetes that I did not know, is that T2DM is largely caused by inflammation. And the cause of this inflammation is the obesity. I was unawares that obesity, on its own, elevated systemic inflammation in such a significant way. Simply being obese elevates inflammation, and this uptick in inflammation can lead to the body's tissues becoming resistant to insulin.

The resultant resistance to insulin can change how blood vessels respond to stimulus, including exercise. With diabetes, the endothelial tissues of the blood vessels (a fancy name for the specialized tissues that line blood vessels) no longer appropriately dilate, which hinders the body's natural responses to exercise. Net result - a person with insulin resistance may feel more tired and depleted from exercise, and then is less likely to stick with an exercise routine. A downward spiral!

Diabetes has become a worldwide epidemic, and while diabetes can be effectively managed, the long-term side effects continue to extract a heavy toll. Diabetes-related issues in circulation can cause kidney damage, loss of eyesight, neuropathy, and amputation... to name a few. Diabetes is a much larger subject than this blog can handle, though I'm hoping that a couple of points can emerge from this brief discussion.
  • Keep moving! In particular, keep up with your aerobic conditioning and strength training. These are the only two paths of exercise/movement that have been shown to both treat and prevent diabetes.
  • Stay trim. While I'm heartened to see the great strides that are being made in body-acceptance, I hope that we don't lose sight of the fact that obesity significantly increases the risks of developing serious health problems. Serious health problems! Staying at a healthy weight remains an important predictor of good health.

Sunday, November 20, 2016

Stuff I Learned - Week #13

This past week I've been learning about how high altitude impacts physical activity. As many of you have probably experienced, hiking in the mountains of Colorado can be more fatiguing than hiking in Wisconsin's Blue Mound State Park. Why is it much easier for a flatlander to exercise in the hills of Southern Wisconsin's Driftless region than to exercise in Colorado's high country?

Atmospheric pressure rapidly decreases as altitude increases, and as a result, there's a lot less oxygen available at Monarch Mountain Ski Area in Colorado than there is at Tyrol Basin here in Wisconsin. While this decrease in available oxygen may seem like the beginning and end of the story, the physiology is actually much more interesting than simply more/less oxygen.

Earning turns outside of Leadville, CO
(huffing and puffing every step of the way)
Let's start with looking at how your body responds to an environment that has less available oxygen (hypoxic). A few weeks ago I discussed the feedback mechanisms that determine respiratory rate, and those same mechanisms are at play in the hypoxic state. With less available oxygen in the inhaled air, the chemoreceptors in the aorta and carotid arteries signal the respiratory centers of the brain-stem to increase the depth and rate of the breathing.

In addition to the increased rate and depth of the breathing, heartrate also increases when you're moving around in the high country. (Have you ever experienced the feeling that your heart was going to fly out of your chest while skiing in the mountains?)

The increase in heartrate and respiratory volume that occurs in the mountains is a good start in adapting to the lower-oxygen conditions, though these cardiorespiratory adaptations are still insufficient to fully compensate for the hypoxia. There is still insufficient oxygen getting to your working muscles - as hard as you may be breathing when you're skiing, it still isn't hard enough!

There's not much oxygen at the top of Mt. Kangchenjunga.
At 28,169 feet above sea level, tying your shoes is exhausting. 
Why, then, doesn't the body just breathe harder? The answer brings us back to the feedback mechanisms that I discussed a few weeks ago. At altitude, the feedback mechanisms are receiving conflicting messages about the hypoxic conditions, and as a result, are sending mixed messages to the respiratory control centers.

As I mentioned earlier, the sensors in the carotid arteries and aorta are sensing a deficit in oxygen, which signals the respiratory centers to increase the rate and depth of the breathing. So far, so good. Unfortunately, the deeper breathing reduces the levels of carbon dioxide in the muscles. While less carbon dioxide in the muscles may seem like a good thing, the decrease in carbon dioxide corresponds to an alkaline shift in the tissues. As the pH of the tissues moves to an alkaline state, the central and peripheral chemoreceptors signal the brainstem to slow down the breathing in order to bring the pH of the tissues back into balance. As a result, the body is simultaneously trying to speed up and slow down the breathing!

Herein is another example of the brilliance/intelligence of the human body. After spending a few days at altitude, your body figures out how to respond. The central and peripheral chemoreceptors reduce their signaling to the respiratory centers, and as a result of this downregulation, the breathing responds more effectively to the hypoxic conditions. Voila - blood oxygen levels are normalized, and some degree of adaptation to high altitude conditions occurs!

While there is more to high altitude adaptation than this cardiorespiratory signaling effect, I think I'll leave the discussion here for the time being.

For a future posting, let me know if you'd find it interesting to learn how Tibetan and Andean populations, for example, have adapted to thrive at the highest elevations.

Tuesday, November 15, 2016

A Pre-Owned, Encore Presentation

When I watched TV as a kid, we would watch reruns at the end of the regular season. Somewhere along the line, it seemed as though the term reruns was outmoded by encore. I'm now hearing previously-aired programming called encore programming.

Similarly with used cars; the car dealers used to have a used car lot, and now they have a lot filled with pre-owned cars. The times change, don't they?

Anyway, this week's blog is a pre-owned, encore blog! I wrote this essay in 2012, and I feel that its sentiment remains relevant in 2016. The divides of our nation remain intact, and have perhaps even strengthened. The following essay reflects some of my thoughts on actionable steps we can take within our yoga community to help rebuild our commons.


The angle of the sun and the cooler nights are a reliable indicator that autumn is upon us. And every four years, the arrival of autumn hearkens the arrival of something more than cooler weather – it announces the arrival of the US presidential elections.

When you live in a town like Madison, WI, politics are an inescapable part of daily life. Whether you’re liberal or conservative (or somewhere in between) it seems like everybody has an opinion – and quite often, a strongly held opinion!

Each election cycle, I’m reminded how individual members of the yoga community often make assumptions about the other members of the community. Because we share an interest in yoga, we may assume we share other beliefs and interests, too. Sometimes that may be the case, though quite often, it’s wishful thinking and/or a projection.

Sharing an interest in yoga may predict elements of behavior, but the vastness of the human experience virtually guarantees that the person on the mat next to you contains multitudes. Unfortunately, I often find members of the yoga community assuming that other members of the community share the same outlook and political beliefs.

When we assume that other people think and believe what we do, we miss an opportunity to stretch our minds. Like an unstretched muscle may retract into stuckness, the unchallenged mind often retracts into rigidity. While we may point fingers to the “other” at the suggestion of mental rigidity, I think it happens on both sides of the political aisle. There is likely to be some wisdom embedded within the various viewpoints, and being able to recognize the wisdom of the “other” can build community more effectively than self-selecting into self-reinforcing groups.

As we enter into another election year, I’m hoping the community of practitioners at Mound Street Yoga Center can keep in mind the diversity of our community. I believe each of us hopes these practices can help us live happier and healthier lives, with less dis-ease and distress. Since it’s likely we’re looking for the same benefits in our yoga, it seems possible that similar motives drive our political beliefs and choices.

As the election season heats up, if we find ourselves inspired to express political opinions within the yoga studio, can we:
  • Express our opinions without insulting or degrading other viewpoints?
  • Listen when we hear other viewpoints?
  • Open our hearts to consider that the “other” likely believes their way is a path to cultivate more happiness and/or healthiness, too?
With these three ideas in mind, perhaps we can come away from this election cycle stronger and healthier. And with the electorate split virtually 50/50, anything that promotes unity and community seems well worth the effort.


Saturday, November 12, 2016

Stuff I Learned - Week #11

Notice how the elbows and knees
hyperextend? The capacity to hyperextend
is a key trait of joint laxity.
It's been awhile since I've written much about my intended research. While research is central to the Ph.D degree, there are a few details that I must address prior to fully delving into research.

Firstly, there's the not insignificant matter of earning an MS degree. Some academic programs consider the Master's degree an essential prerequisite for admission to the Ph.D program, while other academic programs award the Master's degree more or less as a consolation prize. (i.e. -  if the pursuit of the Ph.D goes fully awry, you're ushered out the door with an MS)

The Kinesiology Department here at the University of Wisconsin is in the former category. While my eye-on-the-prize is the Ph.D, I must satisfactorily complete the coursework and thesis for the MS before I can get all fancy-pants and pursue a Ph.D.
People with joint laxity often
have tight muscles overlaying
their loose joints.

While the MS is the immediate-term goal, I'm consistently reminded by my faculty mentors that the dissertation's groundwork is to be put into place right now - this very first semester in school!

And one of the first steps in putting this groundwork into place is to critically review the existing literature on the subject-of-interest. So (drumroll) what is shaping up as this subject-of-interest?

Joint laxity
I'm more interested than ever in the trait of joint laxity, and the anxiety, clumsiness, fatigue, pain, etc. that are often associated with loose joints. The more that I research joint laxity, the more that I find myself drawn into the subject!

Joint laxity and its correlated conditions will be the subject of a review paper that I plan to coauthor early in 2017. Because a fuller outline of this subject is forthcoming, I'm going to just touch on some of joint laxity's salient points in this blog entry.

  1. Joint laxity is a heritable trait, which is to say that you don't acquire joint laxity. Doing tons of yoga won't give you joint laxity, though it's virtually impossible to do fancy/advanced yoga poses unless joint laxity is already present.
  2. Joint laxity correlates to an increased incidence of many conditions such as osteoarthritis, chronic pain, chronic fatigue and anxiety (to name a few). I'm particularly interested in studying the anxiety that correlates with joint laxity.
  3. People with joint laxity often have deficits in proprioception. Put more simply, people with loose joints often have a harder time feeling their body's place in space than people with tighter joints. Emerging evidence is suggesting that this proprioceptive awareness can be trained.
  4. And one of my $64,000 questions: can training the proprioceptive awareness reduce the pain, fatigue and anxiety that often accompanies joint laxity?
Over the past two months I've read numerous scientific articles relating to joint laxity, and I am happy to report that a diffuse research interest is focusing into an intended direction. By the end of this semester I am hoping to complete a workable outline for the review paper. This outline will then form the scaffolding for the first academic paper of my return-to-school era!

Monday, November 7, 2016

Stuff I Learned - Week #10

A recent article on CR
A friend of mine once described his tendency toward ADHD as like being a ferret on crack. While I have yet to directly observe a rodent smoking a Schedule II controlled substance, my friend's metaphor immediately created a mental image that's endured in my mind.

I have a pretty strong tendency toward ADHD. On the rare days that I find open space in my schedule, I often wander from task to task, like a vagabond in my own home. It's only through diligent mind-training (meditation) that I've reined in my random-walk mind in order to accomplish some of the goals that I've set for myself.

Even though I've largely learned to work with my ADHD tendencies, every so often I'm still reminded of my tendency toward this cognitive Brownian motion. Just the other day, I was on the PubMed website looking up a neuroimaging study on people with joint laxity (fascinating, BTW). While on PubMed, an article on calorie restriction (CR) appeared in the sidebar. I've been interested in CR for awhile, and quickly found myself shifting my focus from fMRI studies of the amygdala to discussions of longevity and age-related decline.

The non-ADHD subject of this blog
I've long been fascinated by the increased vitality and lifespan of animals that are fed reduced calorie diets. While the evidence is pretty strong in support of CR benefiting the health of animals (including worms, flies and rodents), the evidence supporting CR for humans is pretty scant.

To help bridge the gap in understanding how humans (and not mice!) may respond to CR, researchers at the University of Wisconsin are running a long-term study of monkeys fed CR diets. While the study is far from complete, the initial results are very encouraging. I think it's too early to draw any conclusions about humans, though the CR monkeys seem to be living longer and healthier than their heavier (but not obese) comrades.

As in many things science, there are different schools of thought on CR. Some studies make it sound like CR is the for-sure, next best thing, whereas other studies suggest that the CR benefits may be limited in humans. In a future blog I'll talk more about how I've adopted some (but not all) CR ideas into my personal approach to nutrition, but for now, I'd like to leave you with my favorite words of advice on food.

From Michael Pollan

  • Eat Food
  • Not Too Much
  • Mainly Plants

Have a great week, and thanks for reading!

Wednesday, November 2, 2016

Stuff I Learned - Week #9

Your respiratory system relies on feedback from your body
to determine the depth and rate of breathing. This diagram is an example of a
mechanical system that also uses feedback.
In last week's post, I briefly discussed how yogic deep breathing isn't necessarily how you should breathe throughout your day. Did you get a chance to view Leslie Kaminoff's video? I got quite a kick out of his story... largely because I have similar stories! But rather than boring you with tales of runs-gone-awry, this week I'll go into a little more depth on the mechanisms underlying cardiorespiratory control.

An example of a feedback loop
In the earliest days of automotive fuel-injection, the fuel was simply squirted into the combustion chamber. (do you remember before there was fuel-injection; when cars had carburetors?) While there was some rhyme and reason to the amount and timing of the squirt, too much or too little fuel was often injected into the engine. When too little fuel was injected, the engine could be damaged from overheating. When too much fuel was injected, the fuel economy would suffer.

The just right balance of fuel/air mixture (the stoichiometric ratio) is imperative for optimal function, and was often elusive. In the earliest days of fuel injection (like the bad-old-days of carburetion), the amount of fuel that was squirted into the engine was calculated on a best-guess based on outdated information. The actual real-time conditions were not taken into account in calculating future actions, and as a result, most cars didn't get very good fuel economy... nor did they last nearly as long as cars do, now.

It wasn't until the latter part of the 1970's that a major advance in fuel-injection technology became widely available - the Bosch Lambda system. The Lambda system had a sensor in the exhaust pipe that measured the content of the exhaust gases. If there was unburnt oxygen present in the exhaust gases, then the injectors would adjust to squirt more fuel into the combustion chamber in the next cycle. And if there was too little oxygen present in the exhaust gases, then less fuel would be squirted during the next cycle. The Oxygen Sensor was a major advance in fuel-injection technology because it introduced feedback into the equation. With the advent of Lambda feedback, the car could adjust its fuel utilization based on a real-time data stream, rather than relying on information based on guesswork.

The Body
Now, you may be wondering, what does fuel-injection have to do with yogic breathing? As is often the case in my circular approach to explaining things, everything and nothing! What Lambda-sond (what Volvo called their version of the Bosch system) has to do with the human body is feedback. Feedback is an essential component of maintaining dynamic balance in any system.

Your body uses feedback to determine the depth and rate of your breathing. Moment by moment your body is checking and double-checking that the correct amount of oxygen, carbon dioxide and other gases are present in your bloodstream. And like the prior example with automotive fuel-injection, your body uses this information (feedback) to make informed decisions on its next-steps. Feedback is essential in maintaining balance in the body.

In the human body, there are just-right amounts of the various gases that are present in the bloodstream. We do not simply want more, more, more of any given gas in the bloodstream. For example, the oxygen content of blood must remain within a very small window. Too much oxygen in the blood is every bit as problematic as too little oxygen in the blood. (hence the terms antioxidants, oxidative stress, etc). Your body automatically regulates your breathing depth and rate to maintain the optimal chemical balance with these three primary sensors, or sources of information: Central Chemoreceptors, Peripheral Chemoreceptors and Neural Input.

It goes beyond the scope of this blog to fully unpack the nature of these sensors, though since I've mentioned them, I'd better at least describe their roles in brief:

  • Central Chemoreceptors live in the medulla (brain stem), and they sense the carbon dioxide (and other substances) present in the cerebral spinal fluid. An increase in CO2 content signals the body to increase ventilatory depth and/or rate.
  • Peripheral Chemoreceptors are located in the aorta and carotid arteries, and also sense CO2 (and other substances) content . Similarly to the Central Chemoreceptors, an uptick in CO2 concentrations signals the body to increase ventilatory depth and/or rate.
  • The Neural Input senses signals coming from higher brain centers, along with sensory information coming from the muscles and joints. This information is also used by the respiratory control super-computer to determine depth and rate of breathing.

These sensors automatically send appropriate information to the respiratory control centers of the brain stem. The supercomputer of the brainstem then processes the incoming data so that you will breath in the optimal way. If you try to override the wisdom of this system you may feel buzzed for awhile. But it's virtually inevitable that the skewing of your blood's chemistry by inappropriate deep breathing will lead to feeling worse than if you simply left well enough alone (DFWI).

In summary, your body is very wise. You're generally best off to DFWI when it comes to functions like breathing. While Yogic deep breathing is a time-tested practice, trying to practice deep breathing in daily life is not likely to cultivate optimal health. Since none of us are consciously aware of the concentrations of all the gases within the bloodstream, how can we possibly do a better job of consciously controlling the breathing than the subconscious already does?

Yoga practice is a time to witness the presence of something quite magical, and perhaps to consider the miracle that is this breath... this one, right here. Please, take time whenever possible to notice that you are breathing, which is very different than controlling or regulating your breathing.

side note - please don't believe the claims that oil companies are suppressing fuel-efficiency technologies. The fact that our cars are regularly getting 30+ mpg from a gallon of gas is a triumph of engineering!

Wednesday, October 26, 2016

Stuff I Learned - Week #8

As a kid, I was famous for picking at scabs and digging up seeds to check on how their germination was coming along. As a result of this chronic tendency to mess with stuff, my father coined the acronym DFWI. Whenever Dad suspected that something impetuous, ill-thought or otherwise lacking consideration of the long-term was in the offing, he simply uttered the acronym DFWI to initiate a conversation.

While my father left this plane almost 10-years ago, I can still clearly hear him saying DFWI. And as a yoga teacher, I still find myself thinking about DFWI when I consider some of the practices that are commonly taught.

Breathing - at rest, during exercise and deepest (yoga pranayama)
Deep breathing is one of the canonical practices of Hatha Yoga. Depending on the style and tradition of Yoga that you practice, deep breathing is most likely at least a part of what you consider yoga. While there are likely many benefits to this deep breathing, it's not a foregone conclusion that deep breathing is necessarily beneficial everywhere else in your life.

A case in point is aerobic exercise. I know that many of you like to bike, run or otherwise enjoy activities that elevate your heart rate. The next time you do so, experiment with trying to maintain your deepest yoga breathing. I think you'll find the experience is exhausting... and your performance may be pretty underwhelming. How to breathe during activities that elevate your heart rate? As my Dad used to say, DFWI!

Why is this? Because your breathing is tied into a complex network of physiological adaptations to exercise. Or, put another way, your body is very smart. When working out, there's a chance to witness firsthand the vastness of the intelligence that permeates the human organism. Even as you sit and read this blog, your body is moment by moment measuring chemical concentrations in your blood, launching any needed immune system responses and modulating your body temperature... and you're not having to think about any of it! The body is boggling in all the processes that occur 24/7 that do not involve our direct control.

Now, it goes beyond my pay grade to identify what this intelligence may or may not be, though I do think that taking some time to bring awareness to this vastness is a very good use of time. And this is what yoga has the potential to do - to provide a theater to observe the wonder that is this human life.

This video is a fun discussion of deep breathing and running. For the time being I'll leave you with this video, and I'll pick up this discussion again next week.

Oh, and by the way, what do you think the acronym DFWI stands for?