The Olympics: In the High, Thin Air

Ever since Mexico City was chosen as the site of the 1968 Olympics, athletes and their coaches all over the world have been concerned about how performance may be affected by the 7,434-ft. altitude. Sportsmen in low-lying Britain and Belgium, with no facilities at hand for high-altitude training, have gone so far as to suggest moving the Olympic endurance events to sea level—say, steaming Veracruz. An eminent American physiologist has proposed that the U.S. establish a base camp, Everest style, on the Mexican coast, and fly athletes to Mexico City on split-second timing to compete during the first hour after their arrival, before the altitude has time to erode their performance.

Both suggestions are probably unnecessary. The basic facts about the influence of altitude have been known for a quarter of a century, ever since U.S. tennis stars began to play frequently in Mexico City. All along, they have reported that for the first few days of competition their game is poor; after ten days to two weeks they begin to notice improvement, though they still huff and puff. Their observations were confirmed and amplified during last October's "Little Olympics," a preview sports week staged by the Mexican Olympics Committee.

Short Haul. Athletes suddenly airlifted from low to high altitude can perform as well as usual in brief events that require only short bursts of maximum exertion. "A trained athlete can run the 100 meters in ten seconds practically without breathing," explains Dr. Daniel F. Hanley of Bowdoin College, chief of the U.S. medical team at the Little Olympics. "You just can't build up any oxygen debt* in ten seconds. And there's no problem at 200 meters or even 400."

Except for cyclists, who find that decreased air resistance can make up for the effects of decreased oxygen for as long as five minutes, a competitor in an event that lasts more than about 1½ minutes will almost certainly turn in a sub-par performance. Says Dr. Hanley: "We found that boxers in Mexico City who were used to two-minute rounds really had problems when the rounds ran three minutes."

The lower atmospheric pressure (about 11 Ibs. per sq. in. at Mexico City's elevation v. 14.7 at sea level) and the reduced oxygen available for exchange in the lungs appear to have no effect on athletes' hearts. Scores of physicians from a dozen countries ran elaborate tests on the athletes in October, and the electrocardiograms were normal. The problem is simply that breathing is less efficient, or as Dr. Hanley puts it: "You get less oxygen per gulp, so you've got to take more gulps to get enough oxygen to the muscles."

Winner by Acclimation. Physicians and trainers will have to figure out the best way to overcome the oxygen shortage. The obvious answer is acclimation. People who are born and raised at altitudes like Mexico City's seem to have no problem, and people who go there to live eventually adapt to the rarefied air. The question that bedevils international physiologists is how long to allow for such acclimation.