Genetics vs. practice for athletic performance

THANK YOU FOR VISITING SWEATSCIENCE.COM!

As of September 2017, new Sweat Science columns are being published at www.outsideonline.com/sweatscience. Check out my bestselling new book on the science of endurance, ENDURE: Mind, Body, and the Curiously Elastic Limits of Human Performance, published in February 2018 with a foreword by Malcolm Gladwell.

- Alex Hutchinson (@sweatscience)

***

Over the last few years, we’ve seen a big shift toward the important of practice — “deliberate practice,” to use the term coined by Florida State psychologist Anders Ericsson — in achieving greatness in pretty much any field of human endeavour, including sports. Books by people like Malcolm Gladwell, Daniel Coyle and Matthew Syed have advanced this “nurture over nature” argument. It’s an empowering message, and perhaps important to counter the idea of genetic predestination.

The problem is that, in many cases, they’re arguing against a straw man. To show that practice — lots of it, perhaps even 10,000 hours — is utterly crucial to the making of a champion is not the same as showing that genetics don’t matter! It seems utterly trivial to argue that you need to be tall to be a great basketball centre, and that no amount of practice will make you taller. And it’s just as inane to argue that height is the only attribute that’s strongly influenced by genetics and also contributes to athletic success. But people like Syed seem to be arguing just that.

Anyway, if you’re interested in the topic, Ross Tucker of the Science of Sport blog has an excellent two-part look at why we can’t ignore the role of genes in sports, and why that role is so complicated that we shouldn’t expect to find a “speed gene” or an “endurance gene,” despite the promises of genetic screening companies (part 1 here, part 2 here).

My only criticism of Ross’s series is that, in the second part, he makes a brief hypothetical digression about the role of genetics in the dominance of Kenyan distance runners. Leaving aside the question of whether it’s true or not, it’s not a hypothesis that follows from the rest of the discussion. He presents powerful evidence that genes must play a role in the ultimate potential of any given individual — but that says nothing about what distribution of genetic variations we’d expect to find in different population groups. If I’d had to wager money, I’d guess that his hypothesis is probably correct. But (as the comments below the blog entry show) by going there he left his arguments open to some quite reasonable criticism, which makes it seem like the whole question is up for debate — when in reality, most of what he says is so irrefutable that only someone trying to sell a “contrary to conventional wisdom” book could ignore it.

Speaking of books — but rigorous academic books rather than pop science — York University’s Joe Baker has co-edited a new book called “Talent Identification and Development in Sport” that was launched this week (press release here). If you’re interested in the actual science on these topics — the role of genetics; secondary factors like birth date, cultural context and population size; perceptual motor skill acquisition and expertise; and so on — then this is place to go.