Ever see one of those Kung Fu movies where the wizened sensei sums up life in a sentence? Something like, "A seed cannot be planted in soil that is not fertile."

That's what a real sensei said to Conch Out Barry Summers of Rockville back in 1988, and that's going to be the motto of this next-to-the-last Fit Over 40 column. The motto is on target, too: Whether beginning an exercise program, losing weight or stopping smoking or drinking, you've got to want change before you can have change.

Fifteen years ago, Alexandrian Ron Mead, for instance, finally decided to improve his looks and his health with some exercise. He started jogging and after six years worked up to little events like the New York Marathon (26.2 miles).

I'm looking at two pictures of him now, one at 33 and one at 48, and let me be honest. At 33 this guy looked like a case of the flu; at 48 he looks like a movie star. Guaranteed every time you take hold of your life. Or at least close.

Desy Campbell sums up our motto slightly differently: "In the real world there are stigmas attached to size." She's not talking about being overweight, either, though her thoughts are as apt in that case.

Topping out just under my ribs, Desy is a "Little Person" who completed both a Washington Conchathon (swim 440 yards, bike 6 miles, run 2) and the Bahamas Conch Man (swim a mile, bike 10, run 4). The events "were tests for my character both physically and mentally," she says, "and none of my friends gave me any slack."

Desy was the next-to-the last person across the finish line on Grand Bahama. Short legs and arms can go just so fast. But do you know what she said? "What many people don't realize is that in the small world, I am tall. A friend of mine says there's one reason I'm short: so the rest of you can keep up with me."

Desy, from the metropolis of Culpeper, just returned from a bike ride through Ireland. She swims three times a week. "You could say I'm physically challenged," she says of her size, "or you could say that I challenge myself physically." Fertile soil is what she is.

As is Ron Hackley. When Ron started training for the 1988 Bahamas Conch Man, he weighed in at 212, had high blood pressure and a cholesterol level that raised the blood pressure of his doctor.

He hadn't exercised in years, either. But at age 50 he started training with that 15-minute walk. Now, at 170 pounds, he doesn't take blood pressure medicine and regularly completes full triathlons. "I've done 10," he says, "and my best accomplishment was in Baltimore: swim nine-tenths of a mile, bike 24.8, run 10. What a sense of accomplishment!"

Wendy Wein, 48, started training for the D.C. Conchathon in 1988 "and although I'm still no Jane Fonda, I am healthier than I've been in the last 10 years."

"I've continued to train, too," she says. Though Wendy never ran until 1988, she's now winning prizes. "I took second place in my age group in a 5K race, and have gotten back into swimming, too." Wendy's race partner and training partner along the back roads of Bowie is her 23-year-old daughter. How long since you've done something athletic with a member of your family? Makes you feel awfully good, regardless of your age.

Take Shirley Wagoner, now 61. Shirley started exercising at 41, and though she no longer finds it possible to run, she stays active, anyway.

"Even with minimal skills and limited fitness" Shirley still skis the "black" -- or expert -- slopes. Last summer she added backpacking to her repertoire. Through the Aiyuttuq Park Preserve on Canada's Baffin Island, with 55 pounds of gear and a sleeping bag on her back, Shirley, a District resident, hiked for two weeks. Haven't you wanted to do something like that?And so what if you don't look like an athlete? "I look like a cow scampering across a field when I do it," says trim and now fit jogger Nancy Richeson of Chevy Chase. Nancy first participated in the D.C. Conchathon in 1988 "with my 3-year-old daughter and her dad looking on and cheering. That support was so important to me! Besides, I believe it sets a good example for my child." Planting seeds again.

But to get harvest, you have to stay at it. "I recently celebrated my 57th birthday with a healthy and invigorating (but unofficial) conchathon," says Robert Alvord of the District. Robert had trained faithfully through the summer, swimming 500 yards, biking six miles and running two "and I decided what better gift to give to myself!"

How did he do? "The overall time wasn't great (so who cares) because I had to skim the leaves and bugs out of the pool first, then change clothes between 'events,' etc. But the important thing is I did it and it felt great!"

That feeling remains, too, as long as you stay active. Rosemary Schwartzbard, 48, a Conch Out and clinical psychologist in Arlington, says she "was a couch potato until January 1988. I decided at that moment to do it and have spent few days since then without some form of physical activity. And when I started running I couldn't make it from one telephone pole to the other!"

"Physical activity," this Conch Out/psychologist concludes, "has greatly enhanced my life and has also had an effect on the lives of many of my patients."

And are you going to argue with a psychologist?

Well, I am going to argue with Barry Summers' sensei, the guy who said, "A seed cannot be planted in soil that is not fertile." That's not quite right, is it? Of course, you can plant the seed in infertile soil. Without the right nutrients, however, it simply won't amount to much.

Think of your health as the soil, and then think of your resolve as the nutrients. And then think about doing something active this wonderful holiday season.