"A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects."
-- Robert Heinlein
If you're reading this, you're probably an endorphin addict.
You've figured out that your body responds to extreme demands by pumping out hormones called "endorphins." Endorphins increase stamina, cut pain, and make you feel amazing!
But like all mind-altering substances, endorphins must be used responsibly. The endorphin-high is the cleanest, safest, healthiest, and most socially responsible way of getting high -- but there are hidden dangers.
The greatest of these is overtraining.
You probably have one sport that really turns you on. This is your passion, this is where you touch infinity.
And this is the sport most likely to injure you.
Does it matter what this sport is? Aren't sports, like distance running, inherently more dangerous? No! In fact, the most dangerous possible activity is watching television. Fat is an injury. Loss of muscle tone is an injury. Collapsed posture is an injury.
Inactivity is dangerous; we're not designed for it.
But I also know this: More people hurt themselves moving computer mice than climbing mountains. Why? Because your body is not designed for inactivity. But it's also not designed for repetitive motion, however undemanding that motion is.
Repetitive motion is also dangerous.
For most animals, this is not a problem. They do a few things extremely well. This is specialization. Horses don't climb trees. Lion's don't throw things. Dolphins don't run.
But specialization usually leads to extinction. Doing one thing extremely well means utilizing one ecological niche extremely well. That niche disappears? So does the species.
Our remote ancestors took a different path.
I want to walk you back along that path. Why? Because I want you to understand how important it is not to act overspecialized. That's not who you are. There's no use pretending. The result can be fatal.
It used to be thought that our bodies evolved in East Africa because of a drying trend. Trees died. Grasslands grew. Bipedalism became necessary. With our hand free, our brains quickly grew to make use of this new opportunity.
But it didn't happen that way.
True, around 2.5 million years ago, weather in East Africa changed dramatically. But it didn't get dry. It got dry and wet and dry and wet -- back and forth with disastrous speed. It got cold and hot and cold and hot -- zigzagging so fast that it was almost impossible to adjust. Species died out by the hundreds. Ecological niches evaporated, morphed into new niches, then vanished in turn.
The best way to survive this terrible time was to be the ultimate generalist -- a Jack of All Trades. It's as if Mother Nature lined up every member of a small troupe of early hominids and said: "OK, everybody who can't swim! Hands up! Guess what? You're all dead!" Then a short time later: "Now, hands up everybody who can't run twenty miles! You're all dead!" And so forth through a long list of activities.
Very soon, you have an animal that does a lot of things surprisingly well. We can run, swim, climb, crawl, jump, throw things, carry things -- and none of this is directly because of an increase in brain size! The body we inhabited by 2 million years ago is almost indistinguishable from the body we inhabit today.
Guided by much smaller brain than ours, this tough, flexible, highly generalized body took us out of Africa and spread our kind as far as Indonesia -- all in evolutionary blink of an eye.
Fast forward to today. Your bones and muscles serve a very different brain, but they themselves are 2 million years old. And they know something that your brain has forgotten: what they were designed for. They are happiest when they follow the old African blueprint: Do lots of things pretty well. Run, swim, climb, crawl, jump, throw things, lift things.
That's a lot like cross-training, yes?
But you really like one sport? No problem. Because of your deep evolutionary history, cross-training will improve your performance at your favorite sport.
Facing a plateau in your performance? Back off a bit. Add other activities. Your body will remember its ancient wisdom, forgive you for pretending to be what you're not, and figure out how to do everything more efficiently - including your favorite sport.
Design a program that feeds your favorite sport with a customized program of other activities. Your plateau will vanish.
And get a dog. They're great coaches.