Category Archives: Science

“Why We Run: A Natural History” by Bernd Heinrich

If I took one thing away from this book, it was this: Pacing a marathon is like making love to a beautiful tree frog. These amphibians stage contests of sustained mating shouts, and those males who can croak all night have the best chance of ending up with Mrs Frog. But many of them stuff it up. Males who are trying to get noticed in the frog chorus often give longer, more attention-grabbing calls. Yet such calls are much more costly in energy terms, and frogs who overdo them typically run out of stamina, hit the wall due to glycogen depletion, and fail to last the night. The steady-paced frogs, standing together, hand-in-hand, have the best chance of winning the mating ultramarathon.

This is a gloriously unique book. Bernd Heinrich is world-class biologist and ultramarathoner, and a man who really wants you to share his love for dung beetles. Heinrich draws on lessons from the animal kingdom to explain the different ways in which nature tackles the challenges posed by endurance activity. By studying phenomena such as the aerobic capacity of antelopes, the cooling strategies of insects, and the migration activities of birds – arguably the greatest ultramarathoners in the world – he illuminates what happens to our bodies when we run, and why humans have evolved to become such superb distance runners.

The tree frogs and lizards get it in the neck in this book though. Just about every experiment into these animals’ VO2 max seems to culminate in the unfortunate subjects getting blitzed up in a blender so their levels of lactic acid can be measured. You should never accept a smoothie off this man.

Heinrich is an entertainingly self-aware nutcase, and the book is structured around his quest in 1981 to win the American 100k championship on his first attempt at the distance. Training with virtually no knowledge of sports science, Heinrich retreated to a cabin in the New Hampshire woods and experimented on himself, using his understanding of animals to test out ideas about diet, pacing and training.

From the bee kingdom, he noticed that flight endurance is almost entirely down to the amount of carbohydrate in a bee’s stomach, in the form of concentrated nectar. An abortive long-run experiment with a quart of honey (hello bushes!) made Heinrich look for other sources with the right mixture of carbohydrate and water. There was one obvious candidate: beer. Admirably casting common sense to the wind in the name of science, he tried drinking a 12oz bottle midway through a 20-mile run. The result? A negative split! Clearly beer is the ultimate running fuel.

Except of course, it isn’t. Those of us who aren’t mad professors living alone in a cabin in the woods can quickly foresee what happens when he tries this in a long race. The plan? One beer every 4 miles. The result? Nausea and a DNF.

Throughout the book there are all sorts of interesting asides and gems of information for the non-biologist. Why do chickens have both white and dark meat? Their legs contain myoglobin, a muscle protein that removes oxygen from the blood and makes it available to the metabolic system. This red meat in the legs is full of slow-twitch oxygen-demanding fibres that assist with endurance. The white meat in the breasts, on the other hand, is rich in the fast-twitch fibres necessary for swift, explosive power, such as bursting into flight in a flurry of feathers when danger approaches. This mixture of white and dark is the reason why chickens can’t fly very far, but can run on the ground forever. By contrast, long-distance fliers, such as geese, have very dark breast meat to assist their wing muscles in flight.

Those who have read Born to Run will be familiar with some of Heinrich’s central findings about how humans have evolved to run long distances, primarily because Christopher McDougall lifted them wholesale from this book. If there is one game-changing development in the history of human evolution, it is our ability to sweat profusely. No other animal can perspire in buckets like a human. This was not just useful so that we could sell Global Hypercolour t-shirts to one another, but also so that we could keep cool when hunting on the African plains. Our non-sweating quarry, by contrast, would slowly overheat as we chased it over many miles. Endurance hunting – chasing antelopes to exhaustion – allowed us to eat meat in abundance, which in turn (so the theory goes) allowed our brains to develop more quickly through access to more protein.

As the author points out, other animals have cooling strategies too, and there was nothing inevitable about the development of sweating. Had we been aerial creatures, we might have followed the example of bees, and regularly vomited over ourselves to keep cool (this justifies my behaviour on a particularly steamy night outside Hussein’s Kebab Van c.1999). Or if we had been carrion birds prone to perching in one spot, such as vultures, we could have developed the party-piece of defecating all over our legs (this does not justify my baby son’s actions yesterday morning). Demonstrating that Germans do indeed have a sense of humour, Heinrich concludes that “anyone who has ever been running hard on a sweltering day will be able to identify with such behaviour”.

Heinrich’s main point in Why We Run is entirely absent from Born to Run though. In his view, endurance hunting and ultrarunning are both manifestations of an evolutionary quirk unique to humans: the pursuit of long-term goals and dreams. Chasing animals to exhaustion takes a very long time, and requires the sort of internal vision that finds the chase itself rewarding, but also allows us to keep the prize/prey in our minds, even when it is out of sight and smell. In Heinrich’s view, “We are psychologically evolved to pursue long-range goals, because through millions of years that is what we on average had to do in order to eat.” Only humans have the mindset to undertake such long-term activities without an immediate reward, and it arguably benefits us in other aspects of life too, such as agriculture and collective government. When we train for months on end to run long distance races, we are experiencing a “substitute chase”, taking ourselves back to those early days when what we wanted most in life was a sweet, tasty antelope. Nowadays, of course, we always have the option of putting it in a blender at the end.

Advertisements
Tagged , , ,

“The Sports Gene: Talent, Practice and the Truth about Success” by David Epstein

My great-great-great uncle William Cayley was a country doctor, infamous for once riding up on his horse to a patient’s house. Peering through the window from his saddle, he intoned to the man’s wife that “he will be dead in 3 days”, before galloping off into the distance. I come from a long line of such consummate medical professionals, so you would think that science and medicine would be in my blood. However, I am the black sheep of my family, the rest of whom all work for the NHS. Somewhere along the line my genetic inheritance took a funny turn, and I ended up being a history geek with a terrible grasp of basic anatomy.

I therefore approach any popular science book with a sense of trepidation, anxious that it will highlight my feeble understanding of the subject. So I do not say it lightly when I pay The Sports Gene the highest compliment in my arsenal: This book is so compelling it will even make you care about Alaskan dogsled racing.

As a jumping-off point, David Epstein takes the current nature vs nurture debate. A number of writers, most notably Malcolm Gladwell in Outliers, have popularised the idea that when it comes to sporting or artistic success, practice is a far more significant factor than innate talent. In particular, the concept of a ‘10,000 hour’ rule has taken root, this being deemed (based on one small study of violinists) to be the approximate amount of time required to master a skill at a world-class level.

Epstein doesn’t dismiss the importance of rigorous practice and the right environment, but his book investigates the other side of the question: is there such a thing as innate talent, and what are the genetic markers for it? While there is no single sports gene that makes someone a talented sportsperson, there are a number of genes that make people more disposed to excel at particular sports.

For example, he tells the story of Donald Thomas, a student from the Bahamas, who took up high-jumping at university for a dare, and within 8 months won gold at the World Championships. Thomas has a particularly long and springy Achilles tendon, something determined by a particular combination of genes.

There are all sorts of astonishing facts in the book. If an American man is 6’2” there is a 5 in a million chance that he plays in the National Basketball Association. If he is 7 foot tall, it drops to 1-in-6. Or how about this: 17 American men in history have run a sub-2:10 marathon; 32 Kalenjin men from Kenya went under that threshold in October 2011 alone.

One point that boggled my mind is that there is often more genetic diversity in single African populations (e.g. the Maasai) than the rest of the world combined. This is almost certainly because non-Africans are mostly descended from a small group that left the continent around 90,000 years ago. This has huge implications for sport. The sheer amount of genetic variation means that Africa is very likely to contain the extremes – the outliers – in a given athletic activity. Africa is potentially where you will find both the best AND worst at any sport – the fastest marathon runner and the slowest.

And the Alaskan dogsled racing? The Iditarod is a 1000-mile race across some of the harshest conditions on earth. In 2007 the sport was revolutionised by a simple discovery; if you breed huskies for their work ethic (i.e. their willingness to pull a sled all day and night) rather than their speed, the race could be won in 9 days rather than 14. Huskies that were pulling at 7mph could beat those that pulled at 15mph, something which previously had seemed counter-intuitive. There’s something vaguely comforting about this; somewhere out there is a sport for me that would reward my ability to grind out the miles, even though I am not the fastest greyhound in the pack (although I was robbed of the senior men’s road title, I tell you, robbed!).

Alas, I am missing the crucial genes. I’m not a dog.

Tagged , , , ,
Advertisements
%d bloggers like this: