Human Limits

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

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Archive for the ‘Elite Sports Performance’ Category

The Real Danger of “Too Much Exercise”

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Dick Fosbury & Who Innovated What?

At the 1968 Olympics in Mexico City, Dick Fosbury went over the high jump bar backwards and won the gold medal clearing a height of 7-4 1/4 (2.24m). Over the next 15 years or so, his Fosbury Flop technique became absolutely dominant. More recently as the world has become more and more obsessed with innovation, Fosbury has started to pop up in advertising campaigns for products that hope to be seen as innovative, and the B-school innovation award circuit can’t get enough of him. What he did is also a cautionary tale about the potentially stifling effects of guidelines, check-lists and metrics on things like the quality improvement and standardization efforts directed at things like medical care.


What Fosbury did and how it happened also offers fuel for both sides of the debate about the role of the solitary genius and inventor in change vs. the role of what might be called the ecosystem the innovator finds themselves in. As a 16 year old high school student in 1963, Fosbury struggled with the standard jumping techniques of the time known as the Western Roll and the Straddle which emerged after World War II. However, as he messed around with an older technique known as the “Scissors” he started to twist and turn a bit and the Flop emerged. The fact he was experimenting practice is not that surprising. Track practices and even competitions are frequently not as rigid and scripted as other forms of sports and many coaches tolerate levels of fooling around that might not be permitted in other places. As Fosbury noted:


“The interesting thing was that the technique developed in competition and was a reaction to my trying to get over the bar. I never thought about how to change it, and I’m sure my coach was going crazy because it kept evolving. I believe that the flop was a NATURAL style and I was just the first to find it. I can say that because the Canadian jumper, Debbie Brill was a few years younger than I was and also developed the same technique, only a few years after me (and without ever having seen me).”


The second thing to note about the track and field ecosystem of early 60s is that there was some institutional memory of the Scissors and there were coaches around who had seen it and done it. So maybe the flop did not seem as weird at the time as we might imagine now, and there are urban legends about people trying what might be called proto-flop modifications of the Scissors in the 1930s.


A third thing to consider is that landing pits improved dramatically after World War II as foam rubber replaced sawdust and sand.   Among other things this led to a rule change that no longer required high jumpers to land on their feet. Improved pit technology was also driven by the development of fiberglass poles that led to rapid increases in the heights and records achieved by pole vaulters. It is one thing to fall 6 or even 7 feet into sawdust and another thing to fall 16 plus feet into sawdust. At some level you can argue that the better landing pits led the way to new high jumping techniques


The fourth thing to realize is that Fosbury was not alone. As he pointed out in the quote above, a year or two after he started innovating in Oregon, a 12 or 13 year old girl in Canada named Debbie Brill figured it out on her own. There is in fact a few seconds of video showing her using the “Brill Bend” at age 13 in 1966. If you talk to track and field people from Canada who are much older than 50 they can be quick to remind you that what you are watching when you watch the high jump is really the Brill Bend.  Here’s the clip:



Finally, Fosbury gets the credit because of his great achievement in Mexico City at the 68 Olympics, however what if Brill had gotten wide exposure on TV for going over the bar backwards first? At least a few male high jumpers like Fosbury, Dwight Stones, and Valeriy Brumel, have achieved enough fame that might ring a bell with casual fans. Can anyone other than serious track nuts name a female high jumper? Would the almost exclusively male coaches of the late 60s have encouraged the guys to try a new technique developed by a teenage girl who could barely clear 6 ft? Would going over backwards have languished in the pre-title 9 purgatory that serious female competitors and achievers were frequently consigned to in the 1960s and 70s?


Dick Fosbury is clearly an innovator.   However, even a brief look at the backstory of what he did tells us more about how innovation happens and diffuses than the conventional aha moment narrative does. The ecosystem matters and so do things like permissive coaches. I wonder if all of the leaders out there who are yapping about innovation are as flexible and open to new ideas as Dick Fosbury’s coaches were.


What is the Purpose of This Workout?

Last weekend I was in Eugene, Oregon participating in a symposium on human performance. A real highlight was listening to 81 year old Dr. Jack Daniels discuss his vast experience training and testing elite runners. This included his reflections and ideas on altitude training and what he learned helping prepare U.S. distance runners for the Mexico City Olympics in 1968. Throughout the talk as he gave examples of what elite runners do, Dr. Daniels kept asking and emphasizing:


“What is the purpose of the workout?”


He commented that if you can’t answer that question then maybe you should rethink what you are doing. As I reflected on this perspective, a number of related questions occurred to me. Here are three to think about:


  1. What is the purpose of this meeting?


  1. What is the purpose of this rule, guideline, or metric?


  1. What is the purpose of this argument?


With my three modifications of the “Daniels’ Question” as a background, I would urge everyone to reflect on their own circumstances and see what modifications you can come up with that might help you navigate your life a little better and more efficiently.



In Marathon Pacing, Men Can Be “Knuckleheads”

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Is Overparenting Soccer’s Grass Ceiling?

The loss by the US to Belgium in the World Cup round of 16 will lead to all sorts of endless speculation about what this means for soccer in the US. As an extremely casual fan who can barely understand why there is not a fixed off-sides line like in ice-hockey, gridiron football, and basketball I think US soccer is a testament to the limits of overparenting. What do I mean?


First, I have been to Brazil and traveled around extensively. In essentially every vacant lot in every neighborhood I saw kids playing pick-up soccer. This was also true in rural areas. Contrast this to the acres of well-manicured fields in suburban America, hyper-organized youth programs, teams named Suburban-United, and minivans galore. The only pick-up games you see are when the immigrant adults show up on Sunday mornings and it is Bosnia vs. Somalia for an hour or two.


Second, drive around “nice” neighborhoods in the US and you see basketball hoops in the drive ways. Have you ever seen a soccer goal? While the NBA is populated by mostly African Americans, it turns out many are not as ghetto as we think. The relentless backyard games played by the Miller family (Reggie and Cheryl) are keys to what made them great players.


Third, all over the country in cities and towns large and small there is “a court” someplace where endless games of pick-up 3 on 3 take place. Everyone interested in becoming a good player knows where this court is and at the better ones you will find a collection of players ranging from solid high-schoolers to people headed to the NBA. Frequently these games have rules like “makers takers”, meaning if you score your team keeps the ball and if your team wins you keep the court. There are no parents, no officials, no fancy uniforms, and no Gatorade on the sidelines. There is also a phenomenon known as “noon-ball” at many YMCAs where in the summer middle aged men give the young guys lessons about holding, hacking, and the finer points of getting an edge. In the parent run world of suburban soccer would this be tolerated? What would happen to Jr’s self-esteem?


Finally, as I watched the US struggle against Belgium to mount attacks I kept asking myself where is the electrifying player who can make it happen? There was no Magic Johnson or Brett Favre to pull it out against long odds the way Lionel Messi did in Argentina’s win over Switzerland in the final minutes. I am also sure that while Magic Johnson and Brett Favre perfected their skills via formal practice, the roots of those skills were developed on playgrounds with no parents around.   My bet is that no one drove Magic to the park in a minivan and taught him the no look pass. The paradox of US soccer is maybe that it has to get less organized to get better. Minivans can only go so fast and take you so far.


Dick Fosbury vs. Guidelines

Over the past couple of years I have argued that the current world wide obsession with “big data” and metrics is going to lead all sorts of people astray in many fields. The related idea is that every human activity can be turned into a quality improvement project with guidelines and check boxes that will reduce error and improve outcomes.   Taken too far these twin beliefs are going to limit the sort of individual mastery and innovation needed to find novel solutions to our problems.


A couple of months ago I gave a presentation at Mayo where I highlighted the problems of too much standardization in medicine and the risk it poses to better patient care and innovation. I used parallels with the high jumpers Dick Fosbury and Debbie Brill who as teenagers in the 1960s invented the ‘flop’ and went over the bar backwards. In the current world would their efforts have been stifled by a compliance bureaucracy insisting they face the high jump bar while going over? What would the “approval process” for this new technique be in 2014? How many other barriers might be thrown up in the current world to stop them from moving high jumping forward by going backwards?


I explore these and related issues in the talk below. It is a long presentation about 40 minutes, but bear with me and I think you will enjoy the questions and observations raised in the talk.




How the Heat Lost to the Heat

The big news in the first game of the NBA finals was the air conditioning failure in San Antonio. This surely contributed to Lebron James cramping up and being unable to play the final four minutes of the game as the Spurs pulled away.

As the game wore on, ice packs and cold towels were used in an effort to keep the players cooler, and Lebron apparently changed his uniform at half-time to try to cool down. Might there have been a better strategy to deal with a warm and humid environment with a temperature that was apparently in the 90s at game time? The simple answer is yes.

When our core temperature increases a degree or two, the internal thermostat in our brains activates nerves to sweat gland and we start sweating. The internal thermostat also activates nerves that dilate the blood vessels in our skin and blood flow to our skin increases. If the sweat evaporates the skin stays cool and the blood flowing to the skin cools off. This evaporative cooling system lets the heat generated inside the body get out. When we exercise we produce more heat, and this heat transfer system is even more important.

So, the problems for Lebron and his colleagues included the heat they were producing while playing, the temperature in the building and the reduced ability of their sweat to evaporate due to the humidity. All of this then probably his lead to a viscous cycle of higher body temperatures, more sweating and more skin blood with the extra sweating not helping to cool the body but instead causing more fluid losses. Any extra skin blood flow might also have led to less blood flow for the player’s muscles.

So, what might have been done differently? First, wear less clothing. Any observer of the modern NBA can’t fail to notice the extra clothing and gear a lot of the players are wearing. All of this extra swag creates a microenvironment that makes it harder for the sweat to evaporate and cool the skin. So, if happens again Lebron, ditch the tights. Second, forget the ice and cool towels, they may feel good but if they are too cold they might actually reduce skin blood flow and make core temperature higher. Third, get some fans. The key to the evaporative cooling system I described above is evaporating the sweat. My bet is that there were high capacity fans somewhere in the arena and the best strategy would have been to have players take their shirts off on the bench while the fans created the airflow needed to evaporate their sweat and keep them cool and ultimately in the game.


California Chrome Goes For It

Last year prior to the Belmont Stakes I did a post on the great race horse Secretariat who won the Triple Crown in 1973 with the most impressive athletic performance I have ever seen or heard of. This weekend if California Chrome can win the Belmont Stakes, he will be the first horse since 1978 to win the Triple Crown.


Humans vs. Horses

Horses in general and thoroughbred horses in specific are remarkable running machines. Secretariat covered 1.5 miles (about 2413 meters) in the Belmont in 2 minutes and 24 seconds and won by about 30 lengths. When I use a race conversion calculator to estimate how fast a human could run 1.5 miles, here is what I come up with using current world records for men from 800 to 5000 meters and rounding to the second.


Distance        Time               Estimate for 1.5 miles

800 m              1:40.91                        5:25

1000 m            2:11.96                        5:35

1500 m            3:26.00                        5:41

Mile                  3:43.13                        5:42

2000 m            4:44.79                        5:47

3000 m            7:20.67                        5:50

5000 m            12:37.35                      5:49


The average of the above estimates is 5:41 meaning that Secretariat covered the distance about 2.4 times as fast as a world class human middle distance runner might.


Maximal Oxygen Uptake

For both humans and horses running really fast for a few minutes requires a high maximal oxygen uptake. This means that the heart has to be able to pump a large amount of blood to the muscles where the oxygen is used to help power the running. The lungs then have to be able to transfer oxygen to the blood as it returns from the muscles. In elite human middle distance runners of 60-70 kgs, the heart can pump somewhere between 30 and 40 liters every minute, and it is not unusual to see such athletes breathing 150 to 200 liters per minute. In these athletes maximal oxygen uptake can be about 80 ml/kg/minute or between about 4.5 and 6 liters per minute when you don’t divide by body weight.


What About Horses?

My colleague David Poole at Kansas State University has done some incredible studies of exercise capacity in race horses. The graph below is from a terrific scientific review article he did with his colleague Howard Erickson on oxygen transport in horses and dogs.   The graph shows the estimated cardiac output and oxygen uptake (VO2) in some notable horses.   These horses weigh about 500kg so they are about seven or eight times bigger than elite human runners. When you take the numbers off the graph Secretariat had an estimated oxygen uptake of about 130 liters per minute! This value is about 20 times greater than that seen in an elite human runner and means that on a body weight basis it was something like 260 ml/kg/minute — or more than three times the values seen in elite humans. It is also one of the major explanations of why he could run 2.4 times faster than a human.   His estimated cardiac output was about 550 liters per minute. For those of you who think in terms of gallons that is almost 150 gallons per minute!   Breathing volumes in the range of 2-3000 liters per minute are also possible in these great animals.




When You Watch

When you watch the race this Saturday the horses will be running about 50% faster than Usain Bolt and 24 times as far. The corporate sponsors of the race aside, the race is really being brought to you by Mother Nature, selective breeding and the physiology of oxygen consumption all working together at the outer limits of biology.