A handful of people made enormous impacts on American exercise habits in my lifetime. Jim Fixx was one of them, and he dropped dead after a jog at the age of 52. Yes, he had a family history of heart problems, and had been an overweight smoker into his 30s, but still … as I recall he had written that anyone capable of completing a marathon could not die of a heart attack. Well, he ran one not long before he died, and sudden death undermined his message.

The other two huge influences were Kenneth H. Cooper, the Air Force officer and exercise fan who published the book “Aerobics” in 1968, just in time to influence all my physical education instructors, and Jack LaLanne, who predated those two and just about everyone else with his message urging us to exercise and improve our diets.

Cooper, now 79, is still alive.

LaLanne died three weeks ago at the ripe age of 96, and was active till near the end of his life, so maybe he and Cooper were on to something and we’re not all idiots for doing whatever exercising we can bring ourselves to do.

LaLanne came from another era and seemed to owe a philosophical/marketing debt to Charles Atlas, the body builder/strongman who advertised in comic books after World War II and talked about his early life as “a 96-pound weakling.”

If you followed the link to LaLanne’s wiki page, you see a photo of him all buff. That would be as Atlas would recommend.

Cooper and Fixx, however, took the fitness movement into the whippet-lean realm where the ultra-runners and cyclists pretty much all live today. You don’t hear about any of them worrying about building muscle mass. It’s more about losing fat, low pulse rates and achieving enormous aerobic capacity.

LaLanne, however, trended in that direction later in his long life and career. And he was particularly influential on the topic of diet. He railed against processed foods long before anyone else of note did. I still remember a moment from his TV show of a half-century ago, when someone asked him what one food he would eat if he could have only one. He said: “Bananas! Because they have everything to keep you alive! They’re the perfect food!”

Was he wrong?

Nearly everything that came out of LaLanne’s mouth seemed to warrant an exclamation mark. He was always fired up and enthusiastic about his message, and his energy came across as much as did his message. For instance, you don’t see Cooper swimming through ports while dragging 70 boats, as LaLanne did to prove his strength.

I remember LaLanne as, really, the first professional nag (well, he was) on the topic of health, diet and fitness. Perhaps he was convincing, perhaps I was particularly susceptible to his message, but I can remember trying to act on his advice at the age of, like 8. Not so much the diet side as the exercise side. Calisthenics, all that.

I don’t know if we owe it to LaLanne, but another undercurrent in American culture in the early 1960s was a sense that American children were fat and inactive. The way several of my teachers described it to us, we city kids were not reaping the benefits of growing up on a farm, as many of our parents did, where exercise was a part of life. We sat around and watched too much TV and ate too much. It was the Eisenhower Administration that created, in 1956, the forerunner to the President’s Council on Fitness, Sports and Nutrition. So it was all talked about quite a bit when I was a child, and the targets for physical achievement to become a “presidential athlete” were jarringly ambitious. Like, 25 pull-ups, etc.

(And the funny thing, all these years later, is that American kids of the 1950s and 1960s were, I am convinced, far more active than they are now. Aside from athletes, it’s been pretty much a continuous decline for a half-century. We may have had TV in the 1950s and 1060s, but we didn’t have video games and social media and hovering parents; we actually went outside and played sports. Of our own volition. Organized by ourselves.)

Anyway, LaLanne got after the nutrition thing pretty hard, and it shaped his later message more than did his “feats of strength” — though he kept those up to remain in the public eye. Remember, when LaLanne really began to be noticed, in the 1950s, even the medical profession thought a diet of steak, eggs and whole milk was a good idea. The emphasis on fruits and vegetables was considered nuttiness embraced by zealots like LaLanne.

And the guy lived to 96, vigorous almost to the end. So, yes, maybe he had many good ideas, though there are those who will always say that moderate exercise, a decent diet and a family history of long lives are more accurate predictors of longevity than are thousands and thousands of miles run and push-ups performed.

So, “good going” Jack LaLanne. You didn’t keel over on us while exercising, and you looked good into your 10th decade. Maybe we will try to keep up our more modest exercise regimes.

During the writing of this entry, I ate an apple. Because of you, Jack.