I hate physical fitness. There is probably a more measured, thoughtful way of putting that, but I can't think of it just now - and, anyway, we don't have a lot of time. You are about to reissue your annual Jan. 1 self-denying ordinance: no more smoking, no more Fritos, no more heavy drinking, no more anything except a no-excuses 2-mile daily run. I have spent the past 14 months in one approximation or another of that condition, having cracked a lifelong smoking habit that was probably the sole support of at least four Kentucky families, gained the inevitable weight, lost it, gained it back, lost it again. At the moment I am holding my own - just barely and with no end of resentment. We have a lot to talk about.

By "we" I mean that part of the population whose every nerve and instinct rejects the ascetic, hungrier-than-thou, sweatly undershirt way of life that is sweeping the country. "I take Winston Churchill's side of the argument," I used to hear myself saying grandly, calling forth an image of that tortoise-shaped and tortoise-aged old man lying abed till noon everyday, smoking cigars and belting brandy. But aping the Churchill life-style. I discovered when I could hardly make the needle move on my doctor's lung-testing machine, does not guarantee longevity, only a certain physical resemblance: You get the wrong aspect of the tortoise.

From which it follows that the key questions for us committed dissolute-niks are these: 1) Is it possible to take Winston Churchill's side of the argument without, in time, coming to look like Winston Churchill? And, 2) if it is not, is it at least possible to achieve a measure of physical fitness (oh, loathsome term) without becoming a roots-and-berries nut, a fanatic, a prig or a cultural fascist ("Do you situps or die")?

Since we all know the answer to the first of these questions, we don't need to spend much time on it. Fat is as fat does, and smoking's a killer. Fat is a misery. Smoking stinks. And, in any case, for smokers the handwriting is, quite literally, on the wall: an epidemic of "No Smoking" signs that point to a day when puffing and dragging in public places will be forbidden altogether.

But since giving up a heavy cigarette habit almost invariably leads to a great Christmas-goose-like fattening up, the awful, dispiriting truth is that you have to take on both indulgences at once. You have, in other words, to adopt at least some part of the regimen and outlook of those people who have been driving you crazy with their Goody Two-Shoes nagging and contempt.

It's cruel fate. I wasn't even aware that there was a problem until shortly after I had graduated second in my class from smoking school (you were judged by quit). Taking a train from New York to New Haven I puzzled a moment and then settled in, for the first time in my life, to the nonsmokers' section of the car., Well, it was only a matter of time, as it always is) before one of them started something over a bad waft. It came up our way from rearward, a pretty good snoutful of vagnant Chesterfield smoke, and one fellow among us started raising hell and summoned the conductor and pretty soon the smoking and nonsmoker sections were trading muttered insults and legal threats. I just sat there, in the wrong place, paralyzed thinking: "These are not my people . . . No, my people are the ones back there smoking and hacking and going 'groog . . . groog . . .groog' - poor things, they'll all be dead by morning."

You get the hideous conflict of my situation. It was a seminal experience, to be repeated in the various health clubs, nonsmoking sections and other staging grounds of my enforced and miserable attempts at wholesome living. What you have here are two kinds of people. For the doggedly abstemious and the long-distance runners, as I get it from the burgeoning literature, first, the head-pounding, coma-inducing run. And this is followed by the sensation of "feeling good." My kind does it the other way around. First comes the feeling good and then comes the ordeal:

I can't believe O ate the whole thing."

"You ate it Ralph."

Thr ordeal, incidentally. does nothing to improve the character of the offender. In fact, the two most fattening things I know of are remorse and self-pity - good, each of them, for at least another thousand-calorie shot.

Since so many people have been driven by one thing and another into the ranks of the disciplined physical-fitness brigade, you might think you would have some trouble distinguishing between those who belong and those who, like myself, are tourists who can't even speak tha language. But there is one fairly simply way of telling who is who. For those of us who don't belong, even the attempts to retrieve our health are unhealthy. I went, for example, from compulsive smoking to appalling overeating to a saccharin-kick diet to a - yes - two-week fast on liquid protein.. In fact, by the calculations of the Food and Drug Administration, I believe I am now technically dead. But never mind. Like those characters in Faulkner, we endure. Or some of us do, anyhow.

It is, in short, possible to make the good fight against fat and nicotine and sloth (you don't want to hear about my early-morning swimming club) without losing either your Falstaffin appetites or your Falstaffian lack of character. For one thing, I have noticed that every time I do start to get - how should I say? - ever so slightly self-contented and superior about the way the battle is going, it suits the good Lord to put something revolting like a pizza or a Twinkie or a Mars bar in my way, so that complacency vanisheds right along with resolve.

George Orwell knew all about the power of the temptation. In his book on the Spanish Civil War, "Homage to California," Orwell described how, across the bleak valleys, from trench to trench, the opposing sides would try to demoralize each other by calling out loud political harangues. But the most demoralizing "caller" he knew took a different tack: "Sometimes, instead of shouting revolutionary slogans, he simply told the fascists how much better we were fed than they were . . . 'Buttered toast!' - you could hear his voice echoing across the lonely valley - 'We're just sitting down to buttered toast over here! Lovely slices of buttered toast!'"

It was a lie, of course, but a lie built upon an ancient human truth: the frailty of humankind, the universal vulnerability of all kinds of high-minded political and philosophical postures to the simple tug and temptation of the senses. It's what got us in this trouble in the first place, fellow slobs. Go ahead and try to beat it before it beats you. If your nature is essentially unascetic, I don't think you're in much danger of losing your human touch. There will always another Mars bar.