Sports Gene By David Epstein: A Must-Read For All Coaches

by Robert Johnson
August 1, 2013

Every wonder how guys or gals on a cross-country/track team can “run next to one another, stride for stride, day after day, and nonetheless turn out” entirely differently in terms of results?

Sports Illustrated writer and former collegiate 800-meter runner David Epstein started wondering that when he was an athlete at Columbia University and has been investigating that question and many other related to athletic performance over the last ten-plus years. Now one of the world’s most knowledgeable journalists in the sports science area, he’s written his first book that explores the keys to becoming a truly great athlete, Sports Gene. The book is being published today (August 1st).

I was given an advanced copy, have read it and highly recommend it. It’s certainly a must-read for all coaches and hard-core running fans out there. I think average sports fans would enjoy it as a well. If I was still coaching in college, I think it would change the way I actually coached and possibly recruited. Now that I’m finished with the book, I’m actually putting my copy in the mail and sending it to my old colleagues at Cornell.

Warning, if you are a fan of Malcolm Gladwell and Outliers and the 10,000 hours rules for success (as I was), you might want to be sitting down when you read this one. As much as many may want to believe it to be true, the facts are 10,000 hours of work isn’t going to turn us all into sports superstars. Epstein doesn’t discount the importance of hard work but he fascinatingly tells you how and why genetics matter.

The good news is there is far from one sports gene, and hard work still is often still very important. But if you haven’t already won the genetic lottery, good luck making it as a pro, as those that have won the genetic lottery and also put in the work will have a huge advantage over the non-genetically gifted who just work really hard.

Epstein traverses the globe and explores what’s the key to success in everything from major league baseball, to distance running, to the Iditarod dog race. A few highlights:

The Key To Success In Baseball: Eyesight?

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What is the key to being a professional baseball player? Reaction time? No. Epstein argues superior vision is a starting point.

Did you know that 50% of Los Angeles Dodgers players in the early 1990s had 20/10 vision? Ophthalmologist Daniel M. Laby, who has worked with both the Dodgers and Red Sox, says each year he encountered several pro baseball players with vision better than 20/9, flirting with the theoretical limit for a human eye. In the real world, how common is that?

Not very. “I can pretty comfortably say that in twenty years of caring for people’s eyes I’ve never seen someone outside of pro athletics achieve that, and I’ve seen over twenty thousand people,” said Laby.

The Keys To Success In Basketball:

Malcolm Gladwell liked to believe that there was sort of a certain minimum height required for success in basketball but after a certain height it didn’t matter all that much. Epstein disagrees vehemently. The taller you are the, the better off you are.

Guess what percentage of American males between the age of 20 and 40 that are 7 feet tall are in the NBA right now?

Epstein thinks it’s 17%.

Yes, nearly one in five.

The Key To Success In Distance Running:

Many people want to believe that the Kenyans are good at distance running because so many of them are born in poverty and run to school. But did you know that marathon world record holder Paul Tergat never ran to school as a kid, played volleyball in high school and didn’t start running until between the ages of nineteen and twenty and still developed into one of the all-time greats?

How is that possible?

Epstein would argue three key points.

Kalenjin have skinny legs but Asbel Kiprop may have the skinniest of them all.

1) Skinny legs. Anyone who has ever seen Asbel Kiprop up close will understand this key point (MB: ASBEL KIPROP – “THE SKELETON RUNNER *How much does Asbel Kiprop really weigh?)

Did you know that researchers in 1998 from the University of Copenhagen’s world-renowned Copenhagen Muscle Research Centre discovered that “the volume and average thickness of the lower legs of Kalenjin boys was 15 to 17 percent less than the Danish boys”? The finding is substantial because the leg is akin to a pendulum, and the greater the weight at the end of the pendulum, the more energy is required to swing it.

Another research team has shown that adding 1/10th of one pound to a runner’s ankle increases oxygen consumption during running by about 1 %. So what does it mean in the real world? Well, because their legs are skinnier a Kalenjin boy has about a one less pound in his lower leg as compared to a Danish boy, “resulting in an energy savings at 8 percent per kilometer.”

As Bengt Saltin, one of the worlds most famous exercise physiologists said, “The relationship seems to confirm that the lower leg thickness expressed in absolute terms is a crucial factor for running economy.”

Later Henrik Larsen, another researcher in the Copenhagen group declared, “We have solved the main problem” of Kenyan running dominance.

2) Coming from an ethnic group (Kalenjin) that spent most of its existence at sea level and only recently migrated to altitude + 3) Being born and raised at altitude.

Most Kenyan distance runners are Kalenjin – a tribe that makes up only 12% (4.9 million) of the country. The Kalenjin only recently migrated to living at altitude, so they are bigger altitude responders as compared to ethnicities who have been living at altitude for much longer (maybe someone in the Himalayas?).

As Epstein explains, “A helpful combination, perhaps, is to have sea-level ancestry – so that hemoglobin can elevate quickly upon training at altitude – but to be born at altitude, in order to develop larger lung surface area, and then to live and train in the sweet spot. This is exactly the story of legions of Kalenjin.”

Being born or at least raised at altitude is key no matter whether you are Kenyan or American like Ryan Hall (who was born and raised at altitude) as “altitude natives who are born and go through childhood at elevation tend to have proportionally larger lungs than sea-level natives.”

Why do whites dominate swimming and blacks basketball?

Epstein literally travels all over the globe taking him wherever the science takes him. And he’s not afraid to address topics that many scientists are almost scared to talk about.

Epstein does a great job of trying to calm people down before talking about genetic differences. After all, most people aren’t afraid to recognize genetic differences between the sexes. Did you know that if you took 1,000 men off the street, 997 of them would be able to throw a baseball faster than the average woman and that the world record for fastest pitch ever thrown by a woman is just 65 mph?

Before talking about the genetic differences between ethnicitities, he reminds everyone that we are all very much the same – 99 to 99.5% the same – two eyes, two ears, one liver, two kidneys, etc. But the small differences between people make huge differences at the elite levels of sport.

Why are there way more blacks in the NBA than whites? Well, most NBA players have really long arms and blacks have longer extremities than whites on average.

The average person on the street has an arm span that is equal or nearly equal to their height, but not in the NBA. The average arm-span-to-height ratio of an NBA player is 1.063. The traditional diagnostic test for Marfan syndrome, a disorder of body’s connective tissue which causes elongated limbs, was 1.05. Anthony Davis is 6’9.25″ tall but has a 7’5.5″ wingspan.

Studies have shown that for any given sitting height – “the height of one’s head when one is sitting in a chair” – people of African ancestry tend to have legs that are 2.4 inches longer than those with predominately European ancestry.

Those long legs (and arms) help in basketball but hurt in swimming.

Why is swimming dominated by whites?

Well, given their relatively shorter legs, whites have a center of mass (roughly your belly button) that is 3 percent lower than blacks, which results in a 1.5% speed advantage.

Leg length also seems to be helpful in track and field as well.

One of my favorite lines in the book was when Epstein at one point asks, “Did you know Michael Phelps, at 6’4″, reportedly buys pants with a 32-inch inseam, shorter than those won by Hicham El Guerrouj,” 5’9″?

Similarly that Danish study comparing Kalenjin and Danish boys from 1998 showed that Kalenjin boys were on average two inches shorter than the Danish but had legs 3/4ths of an inch longer.

Lots More

The book has a lot of other great stuff in it, including a huge part that answers the initial question of how can a group of people train exactly the same but end up with vastly different results.

Basically people start at vastly different levels of natural fitness and also people vastly differently respond to training.

Separate studies have been done by scientists over the years with both endurance athletes and weight lifters where the athletes are given exactly the same training regime. The results of the studies have been similar in their basic conclusions.

Some athletes respond a ton to training , some respond a little, and some don’t improve at all (muscle mass increased by 0 to 50% for some weight lifters, similarly VO2 max increased 0% for 15% of cyclists, but also 50% for 15% of cyclists). Yes, that’s right. Some people can lift weights and put on zero muscle mass (throws coaches, you might want to pause before you rip some kid for not working hard in the weight room simply because he hasn’t gotten bigger). Some people can ride a bike for weeks and gain zero in VO2 max.

Some athletes start off with a very bad VO2 max but improve astronomically. One scientist called these type of people “Trainability bombs” – they are just waiting to respond massively to training (miling great Jim Ryun was like this and Epstein has a part of the book devoted him).

The sweet spot for a distance coach would be to find someone who is in the “naturally fit category” (six out of 1,900 people have the VO2 max of a collegiate distance runner with zero training) who is also a huge responder to training – “a trainability bomb.”

What’s the probability that someone is highly endowed and highly trainable? “Between one in one hundred and one in one thousand.”

Go Buy The Book

There is a lot more stuff in the book. Everything from why Paula Radcliffe never won Olympic gold and why some track coaches should just let their best sprinters slack off at practice. But I’ve already written enough. I don’t want to tell you all that is in it (not that I could as it’s 294 pages) as I want to encourage you to go out and buy it.

Yes, I’m biased as Epstein has become a good friend over the last decade as there are only a few journalists left to bump into at major track and field meet events, and even fewer that share my enthusiasm for wanting to talk about who or who may not be doping, but I definitely think it’s worth reading. As Sports Illustrated‘s Jon Wertheim said on the back cover of the book, “you will never watch sports the same way.”

(Gratuituous plug for Wertheim – I loved his book Scorecasting).

Epstein’s book is not quite as fun or smooth read as Malcolm Gladwell’s Outliers, but that’s because Epstein is a scientist at heart (he has a masters in Environmental science) and science is complicated and messy. However, Epstein does a great job of trying to make the science understandable and not intimidating.

Gladwell was willing to sacrifice science a bit for the sake of producing a flawless, inspiring read. Epstein goes more where the science takes him. According to Amazon, Outliers was 287 pages with 10 pages of notes to back up what was written. This book is 294 pages with 34 pages of notes to back it up.

More: Wall Street Journal Review of Sports GeneBorn In First Place
*Business Week Review of Sports Gene
*Excerpt From Sports Gene In Sports Illustrated: Why MLB hitters can’t hit Jennie Finch and science behind reaction time
*Q&A with David Epstein on Runner’s World
*David Monti Q&A With David Epstein On “The Sports Gene”

Note: LetsRun received nothing to write this review and Epstein doesn’t even know we wrote it. We do receive a commission from Amazon if you buy the book.

Other book reviews by can be found here.

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