Human Limits

Exploring performance and health with Michael J. Joyner, M.D.

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Archive for March, 2014

The Politics of Life Expectancy & Lifestyle

Eventually the official retirement age for things like Social Security and Medicare is going to have to rise. The simple reason is that the ratio of workers to “retired people” will drop low enough (about 2 to 1 in the U.S. by the middle 2030s) that the programs will be unsustainable both financially and politically as younger generations balk at paying the bill for a wave of older baby boomers.


A related topic is that increasing the retirement age is fundamentally unfair to baby boomers who are less well educated and less well off.  The idea is that the big increases in life expectancy projected for the boomers will go mostly to people who are better off and stagnate for the less well off.  Also the US is not alone and the problem of keeping “state sponsored pensions” solvent is occurring all over the developed world.  There is no easy way out of this and none of the solutions like reducing benefits, raising the retirement age or raising taxes are exactly politically attractive.


Life Expectancy Differences: Who is Responsible?

The effects of socioeconomic status on life expectancy are also complex, but at least some of it has to do with straight forward behaviors like not smoking.   Incredibly, the poor who can least afford to smoke, continue to smoke at high rates while smoking among the well off and well educated has fallen dramatically:


“Total cigarette smoking prevalence varies dramatically between counties, even within states, ranging from 9.9% to 41.5% for males and from 5.8% to 40.8% for females in 2012. Counties in the South, particularly in Kentucky, Tennessee, and West Virginia, as well as those with large Native American populations, have the highest rates of total cigarette smoking, while counties in Utah and other Western states have the lowest. Overall, total cigarette smoking prevalence declined between 1996 and 2012 with a median decline across counties of 0.9% per year for males and 0.6% per year for females, and rates of decline for males and females in some counties exceeded 3% per year. Statistically significant declines were concentrated in a relatively small number of counties, however, and more counties saw statistically significant declines in male cigarette smoking prevalence (39.8% of counties) than in female cigarette smoking prevalence (16.2%). Rates of decline varied by income level: counties in the top quintile in terms of income experienced noticeably faster declines than those in the bottom quintile.”


You can basically modify this paragraph for almost any relevant health behavior and come up with similar conclusions about who is “doing better” where; or what socioeconomic subgroup is following health guidelines about body weight, diet and exercise as well as smoking.


Sooner or Later

It is just a matter of time until Social Security and Medicare along with similar social insurance and state sponsored pension schemes in other countries will bump up against a demographic wall. So, in the discussion about the changes needed to keep these programs viable, at what point does personal responsibility factor into the policy discussion and political debate?  This is especially important because almost all key health behaviors are independent of access to medical care.



Triangulating Phil Jackson

The news that the basketball coach Phil Jackson is taking over the NY Knicks has focused on Phil-as-Zen-Master and what he can do for a dysfunctional organization that seems devoted to mediocrity.  Part of this discussion includes some contrived controversy about the Triangle Offense, a scheme that he used with great success while coaching the Chicago Bulls and Los Angeles Lakers to 11 NBA championships.   Will Phil hire a coach who runs “the Triangle” and if so, will it work without Michael Jordan of Kobe Bryant?


The Triangle Evolves

My high school team ran the Triangle (known as the Triple Post then) and over four years we won >90% of our games and went to state year after year.   I can still diagram the basic Triangle set and various options that flow from it.   The “inventor” of the Triangle, Tex Winter has called it a “junior high offense” and freely admitted that his ideas about evolved from the scheme he ran under Coach Sam Barry at USC.   Below is a diagram  of what the offense looks like after the first option.





What the Triangle Does

The triangle does a number of things:

  • It gets everyone involved.
  • It emphasizes spacing and facilitates passing.
  • It sets up a series of simple 3 on 3 and 2 on 2 sub-plays that eventually let the offense find a mismatch that leads to a good shot.
  • It is a framework and is not rigid; each player has reads and options.
  • It has continuity and there is always a way out and another option.


If you take these five good things about the Triangle and try to apply them in a general context it looks like a pretty good way to manage or lead most things in life……get everyone involved…..facilitate teamwork……look for and leverage small advantages……have a system but be flexible…..don’t get in situations where there is no good option.


Only Works for Phil?

One criticism of the Triangle is that it has “only worked” for Phil Jackson who had great players.  While that might be true over the last 20 or so years, the Phoenix Suns led by Winter disciple Cotton Fitzsimmons ran the Triangle in the early 70s and generally over performed with an expansion team.  The other thing that people forget is that in an earlier generation both Alex Hannum and Bill Sharman (who played with for Barry at USC) used elements of the TriangleSharman, who recently died, is one of the greatest athletes and pure shooters to ever play in the NBA, he was a superb coach and is one of only three people in the basketball hall of fame as a player and coach.


Steve Kerr’s Final Word

Steve Kerr who was on five championship teams with the Bulls and later the San Antonio Spurs mastered the Triangle as a player.   He had the following comments about the Triangle:


“You can’t afford to have the ball in one person’s hands. In a way, that is sort of the genius of the offense and the reason it makes it so difficult for a lot of modern-day players to adapt…….It’s alarming that so many coaches have tried and not had success, I’ve had this debate with myself since I’ve thought about coaching at some point in my life, and if I were to do so at the NBA level, I’m not sure I would implement the triangle. I believe in spacing and ball movement and angles and backdoor cuts and using the defense’s pressure against itself. Those are all things the triangle does. But it’s a little tricky because it does take time for the players to adapt and really feel confident with it, and one thing NBA coaches don’t have is time. If they mess around trying to run the triangle for a year or two and they don’t have success, then that’s it.”


If no one runs the Triangle it is not exactly a threat to Western Civilization, but maybe the fact that no one is running it highlights a world where short term thinking “wins” all too often.



Does Exceptional Talent Run in Families?

Last week I explored why it is easy to conclude that talent might be highly heritable but hard to get an easy DNA based read on the genetics of talent.  In this post I want to share some thoughts about how exceptional levels of achievement and success seem to run in families and ultimately why this might increase through a process known as “assortative mating” or the tendency of people with certain characteristics to reproduce with each other and perhaps amplify the characteristic of interest over time.  Think tall people marrying tall people and having tall kids for example.  This concept also applies to things like income, intelligence, and unfortunately obesity.


This post also reflects an e-mail discussion with the usual suspects:  David Epstein, Jonathan Wai, Amby Burfoot, and Terry Laughlin.


Darwin’s Family

During some recent academic work on heritability and genetics I stumbled onto the fact that Darwin’s extended family has been loaded with achievers and innovators for about 250 years.  Other families of note include the Huxley family and also the Bohr family from Denmark whose members have made major contributions to physiology and math with two Nobel prizes in physics.


Sports Dynasties

When dynastic families in sports came up, through dumb luck David Epstein was looking through the files he generated on this topic for his book “The Sports Gene”.  Here is David’s stream of consciousness list of exceptional families and a few side comments:


“In the course of book reporting, I came across a lot of families with multiple pro athletes, although not always in the same sports. For example, Jon Jones is the greatest MMA fighter in the world, and his two brothers are NFL players. Then there were rare families like the Alou clan, which had like six straight men in MLB. At one point, three Alou brothers were the outfield for the San Francisco Giants. The Alomars had father and two sons in MLB, and the Bells had four guys in three different generations who all at one point played for the same team! The Boones, Hairstons, and Colemans are three generation MLB family. Clay Matthews’ family is a three generation NFL family. I remember a father and son from the Maldini family in Italy were captains of Champions League winners exactly 20 years apart. I guess there are a few really high profile ones, like the Mannings, the Harbaughs and Ryans, the Sharpes. The Gronkowskis have three currently in the NFL. Cecil and Prince Fielder. In the NBA the Gasols, Brooke and Robin Lopez, the Currys. Kobe and his father (Joe Bryant). Barry Bonds and his father. Rick Barry and his three sons were all in the NBA. I think the Staals have four brothers in the NHL. Eight members of the Sutters have six Stanley Cups between them, and I think the three Howes have some. And I only know the Sauers have two brothers in the NHL and one was in the NFL because I was writing about the brain damage of the NFL brother. There are some prominent identical twin athletes, like Tiki and Ronde Barber, and in track the female Barbers, and the Borlees. The Klitschkos, both world boxing champs at the same time. The identical Bryan bros are the top doubles tennis team in the world. The Griffeys, the three Dimaggios, the three Ripkens. Jackie Robinson’s brother took silver in the 200 in 1936 just behind Jesse Owens. The Alis and Reggie and Cheryl Miller both have a male and female who were both the best or nearly the best in the world. The five Andrettis in auto racing. The Williams sisters of course. …there are a bunch more. I didn’t memorize this, I was just pulling some from a folder where I had been marking these down. Actually, my favorite was an Israeli mother and daughter who were on THE SAME 4×100-meter relay for the national team. How cool is that?”


Basketball Fathers and Sons

David also sent me some back of the envelope calculations made by his colleague Jon Werthheim (Scorecasting)  about the odds of the son of an NBA player making it to Division 1 college basketball:


“We can argue about the ratio of nature to nurture. But, clearly, sons born to fathers who once played in the NBA are statistically more likely to become D-I hoops players. How much more likely? After joining forces with Dr. Ed Feng—Stanford Ph.d in engineering and founder of —crunching the numbers, and making some admittedly imprecise assumptions, we reached an astounding conclusion: male offspring of former NBA players are currently more than 55 times likelier to earn a college basketball scholarship than a male from the population at large.  Here’s how we arrived there:

• There are (roughly) three million high school graduates each year.

• There is (roughly) a 1:1 male-to-female ratio for 15-64 year olds.

• So there are 1.5 million male high school graduates each year

• Division-I college basketball teams have up to 13 scholarships

• There are 347 Division-I schools that have a men’s basketball program.

• Overestimating that each program uses its full complement of scholarships, there are 4511 scholarships at any given time, 347 * 13 = 4511.

• We divide the 4,511 scholarships by the 1,500,000 males times four years of college. i.e. 4511 / (4 * 1,500,000) = 0.00075.

• In the population at large, a male’s odds of earning a D-I basketball scholarship are .00075 or 1 in 1330.


On the other hand:

• There have been 4,699 players in NBA history. (This, however, dates to the 40s and includes current rookies.)

• We make a rough estimate that one-tenth of them had a male offspring born between 1990-1994 — the window for kids in college today.

• So 470 former NBA players had a son born between 1990-94.

• There are (at minimum, as some parentage might be unascertained) 20 current D-I players whose fathers played in the NBA.

• 20/470 = 4.3 percent.

• Among the population of current 18-22 year-old old males born to NBA players, their odds of earing a college scholarship are roughly 1 in 23.5.

• Put another way, they are more than 55 times more likely to play D-I basketball than kids whose father weren’t in the NBA.


When Elites Meet and Mate

Before there were a lot of high level athletic opportunities for women it might have been unusual for elite male and female athletes to meet and mate.  However, with the advent of more competitive opportunities for women perhaps there will be more and more pairings of elites and whatever elements of athletic success are heritable might converge in their kids.   Amby Burfoot pointed this out back in 2008 for the runner and 10k bronze medalist Shalane Flanagan who both “Picked Her Parents Well” and “Trains Her Butt Off”:


“I’ve been writing a bit in recent days about possible genetic contributions to distance-running success. You know: “Pick your parents carefully, and ask them to grow up in the Rift Valley of East Africa.” Flanagan didn’t follow the script precisely, but she sure as hell did a fine job selecting her parents. Her mother, Cheryl Treworgy, was the first woman to break 2:50 in the marathon. The first. Ever. Her father, Steve Flanagan, was a 1:50.8 half-miler, a 4:07 miler, a three-time member of the U.S. World Cross Country team, and a 2:18 marathoner.”


Another example is the cyclist Taylor Phinney, his father was a professional cyclist and his Mom (Connie Carpenter-Phinney) was both a summer and winter Olympian in cycling (gold medalist 1984) and speed skating.  Height obviously matters in basketball and my wife has two former teammates who are both about 6-4 (195cm).  Both of these women have married tall (6-6 and 6-8) men who played college sports and their kids are literally off the charts in terms of height.  It will be interesting to see where their interests lie and how far they go in sports.


Nature, Nurture, Push, Pull?

In a whole series of posts on the topic of talent vs. practice I have favored the idea that talent is hard to define but essential for elite (as opposed to expert) level performance.  I have also argued that talent is nothing without practice.   The examples above also make me think about the role of enriched environments.  If you listen to the parents of elite performers in various fields many will tell you that they did not “push their kids” and that the kid pulled them.  However, if you look further you might also find evidence of what I call an enriched environment with plenty of opportunities for exploration and good early instruction.  Also what role does seeing a parent or parents early in life training or pursuing some other activity they really enjoy (that is also valued by the world at large) have on the ultimate motivation of a child?  Late in life Andrew Huxley, who won the Nobel Prize for figuring out nerves work with his colleague Hodgkin, was interviewed and commented about his very early education and home environment:


“Well, I had always been keen on and quite good at hand work of various sorts, played a lot with meccano and zero-gauge clockwork railways when small. My parents gave my brother and me a quite good lathe when I was about twelve or so, which I still have (he was 79 at the time of this interview). It’s a screw-cutting, metal-turning lathe, which I still use for building my own equipment and I was self-taught on that…”


Huxley did design and build much of the equipment he needed for his ground breaking scientific work.  If you read the whole interview it is pretty clear that he pulled and his parents facilitated while he was exposed to the best educational institutions and minds available in England throughout his life.


Lessons for Parenting?

One thing that hits me as I review these family histories of achievement is that pushing your kids and so-called “Tiger Parenting” is not such a good idea.  Maybe a better strategy is to set a good example by engaging the world in a positive but rigorous way and facilitating and supporting your kid’s interests.  From what I can tell that pattern is common in many of the families mentioned above.


Is Talent Genetic?

I have done a couple of recent posts on the idea that practice (the so-called 10,000 hour rule) is more important than talent in reaching elite levels of performance.   The main conclusion from all of this is that practice can make most people really good at most things but talent (and also exposure to given activity) are required for truly exceptional levels of performance.  When the topic of talent comes up the assumption is that it is inherited from our parents and other ancestors.  This then leads to the idea that talent is genetic and that eventually genes that confer the chance for exceptional performance are out there waiting to be identified.
You can take the same general line of reasoning and apply it to things like height, weight, or even your risk of getting certain diseases like high blood pressure and diabetes that tend to “run in families”.


Let’s Start With Darwin

Charles Darwin’s ideas pre-date the concept of genes.  He made lots of observations about how animals vary from place to place and adapt to their environment.  One of fundamental ideas is that via the process of natural selection, animals and plants best suited to their environment are more likely to survive and reproduce.  This reproductive success is dependent on the transmission of key characteristics to the offspring which increase their odds of survival.   When this happens generation after generation certain composite traits called phenotypes emerge.


Galton is Next

After Darwin, his cousin Francis Galton came along and started to make statistical estimates of heritability for things like height and intelligence.  His observations showed a strong correlation between parents and offspring for many phenotypes and he commented that:


“I have no patience with the hypothesis occasionally expressed, and often implied, especially in tales written to teach children to be good, that babies are born pretty much alike, and that the sole agencies in creating differences between boy and boy, and man and man, are steady application and moral effort. It is in the most unqualified manner that I object to pretensions of natural equality. The experiences of the nursery, the school, the University, and of professional careers, are a chain of proofs to the contrary.”


Galton’s statistical work was later extended and amplified by Pearson and Fisher who are familiar to anyone who has ever taken a basic statistics class.  The figure below is from a paper by Fisher in 1919 showing his estimates of how height was inherited from parents and earlier ancestors.




The First Version of Genes

About the same time that the statisticians got busy the work of Gregor Mendel was rediscovered.  Mendel did breeding experiments with peas of different phenotypes and showed via so-called “laws of inheritance” how the various characteristics were transmitted from generation to generation.  None of his observations could be explained in a satisfactory way by earlier ideas about how phenotypes were transmitted from generation to generation.  In about 1909 Wilhelm Johannsen came up with the idea of both genotype and phenotype and:


“Johannsen’s most notable experiments concerned his so-called ‘pure lines’ of the self-fertile princess bean, Phaseolus vulgaris. Studying the progeny of self-fertilized plants, he selected the character of bean weight and found that both the lightest and the heaviest beans produced progeny with the same distribution of bean weights, i e they were genetically identical. He concluded that the variations in bean weight were due to environmental factors and he introduced the terms genotype (for the genetic constitution of an organism) and phenotype (for the characteristics of an organism that result from the interaction of its genotype with the environment). Johannsen favoured the view of de Vries that inheritance was determined by discrete particulate elements and abbreviated de Vries’s term ‘pangenes’ to ‘genes’.”


In this view we have the idea that genotype = phenotype with some modification by the environment.  It also explains why Fisher assumed his estimates of the heritability of height could be explained by this early definition of “what is a gene”.


Genes and Evolution

The ideas about the statistics of heritability, genes and the fossil record were then integrated in the 1930s and 40s into something called the “Modern Synthesis” of evolutionary biology:


“The synthesis, produced between 1936 and 1947, reflects the consensus about how evolution proceeds. The previous development of population genetics, between 1918 and 1932, was a stimulus, as it showed that Mendelian genetics was consistent with natural selection and gradual evolution. The synthesis is still, to a large extent, the current paradigm in evolutionary biology.”


The Changing Definition of a Gene

What happens next is that DNA is discovered and the more general version of a gene is replaced by one based on the idea that DNA is a “read only” genetic code and that has been oversimplified to infer that DNA = phenotype.  There is actually something called the “Central Dogma of Molecular Biology” that has been perhaps unwittingly over extrapolated to infer that DNA=phenotype.   The term “Central Dogma” also has a strangely medieval religious ring to it.


However, it turns out that the genome and the products coming from it are subject to all sorts of environmental influences and that the idea of a linear – one way street – transfer of information from gene to protein to phenotype is a gross over simplification.  There is even evidence that acquired characteristics can be inherited.  These newer ideas about what might be described as a more flexible genome also explain why it has been so hard to find discrete DNA snippets that fully or even mostly explain many things including the statistical estimates of heritability exceptional longevity, height, BMI, intelligence and the risk for many common diseases.


For those of you who want to take a deep dive into these issues the link below is to a lecture by Denis Noble who has argued for a far more nuanced view of how genetic information is converted into phenotypes and how this influences how phenotypes are inherited from one generation to the next.





Back to Talent

Many human characteristics including things that might be called talent have a high statistical probability of being inherited from our parents and ancestors.  When the pre DNA definition of gene is used, then it is pretty easy to think about a sort of non-specific genetic explanation for them.  However, when the DNA based definition of a gene is used it is hard to find discrete or obvious DNA based genetic explanations for most things.  So, don’t expect a blood test anytime soon that is going to tell you that your kids are can’t miss at anything, and even if they have all the “genetic” talent in the world will they get exposed to what they might be great at and will they be willing to practice both intelligently and relentlessly?  The author Aldous Huxley (Brave New World) who comes from a long multi-generation family line of exceptional achievers said:


“There is no substitute for talent. Industry and all its virtues are of no avail.”


On the other hand a standard concept from the sporting world is that you “can’t coach desire”.

Perhaps the truly elite performer in any endeavor needs to have it both ways.