Pulling Against Time

While the performance of nearly all the body's physiological variables goes down with age, the decrement in athletic performance depends on the sport and the athlete's baseline fitness and skill. Exercise physiologists have studied this for many sports and come up with many interesting observations.

One study looked at the top 10 performances for four different length races run by U.S. Masters Swimming in 1976, 1986 and 1996. Masters are amateur swimmers, all older than 18 but most in their 30s, 40s and 50s, who race against one another in five-year age groups. Nearly all the times were faster in 1986 than in 1976; and in 1996 more than half were faster than they had been in 1986. Interestingly, the average age at which finishing times began to rise -- a sign that the swimmers had passed their peak performance -- went from 33 in 1976 to 40 in 1996.

Conclusion: The whole population of adult competitive swimmers is getting faster, and the average swimmer is staying fast longer.

Other studies looked at football and baseball, sports in which cardiovascular fitness is less important to overall performance than it is in such activities as swimming. Age makes little difference in the performance of punters in the National Football League, but the passing success of quarterbacks improves significantly between ages 22 and 26. For professional baseball players, the number of hits a batter gets and the number of strikeouts a pitcher gets both peak at age 27. But the percentage of times a player walks peaks at 30, fielding percentage peaks at 31, and the earned run average (ERA) for pitchers peaks at 29.

Conclusion: Experience and practice counts (even if you're really good) and can make up for loss of strength.

A study of triathletes in their 20s, 30s, 40s and 50s competing in a half-Ironman race found that performance for each part of the event (swimming, biking, running) declined at roughly the same rate in each age group. A study of weightlifters showed that upper-body strength (measured by the bench press) declined at the same rate as lower-body strength (the squat).

Conclusion: No part of your body is spared the effects of age. So exercise it all.

That last piece of advice is the thing that falls out of the vast, detailed understanding of exercise physiology of the past 90 years. Aerobic capacity and muscle strength can be improved with exercise even when people are in their 80s.

Peak performance for most sports may occur in a person's 20s or early 30s, but "in terms of the trainability of the tissue, that seems to be maintained even when the person has another 50 years on their bones," said Edward T. Howley, a physiologist and exercise researcher at the University of Tennessee in Knoxville. "It's never too late to start an exercise program."

Still, the fact that it may be too late to win a race is a hard thing to accept. Especially if you are used to winning races.

Every Thanksgiving morning, Mike Teti, the Olympic rowing coach, runs a cross-country race with members of the Schuylkill Navy, a group of people affiliated with the clubs along Philadelphia's famous Boathouse Row.

The race has been run since 1899, and the field is always fast. Teti has won it nine times, more than anyone else. His best time over six miles was 29:55. Now he comes in at 35 or 36 minutes.

"We remember what we could do. I remember that I could run 5:30 miles. We think we can do it because we could 10 years ago, and we just can't," he said wistfully last week.

Two years ago, he reached another milestone in the Thanksgiving run. A woman beat him.

"Not," he adds after a pause, "that there's anything wrong with that." ·

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