NEW YORK — THE most popular new item at the local ``Y'' is something called the Stairmaster. It is a mechanical device with two moving platforms, electric-powered, that simulates the exertion of walking up stairs. The Stairmaster is a great workout. Still, that people wait in line for it is a bit strange. Stairs are hardly in short supply in Manhattan. People can climb them all they want at their office or apartment building, and for free.
The Stairmaster is another example of the genius of American enterprise in creating a sense of lack amid plenty, and of converting needs and desires once fulfilled naturally - in this case, by walking or climbing - into something to buy.
``We get to buy back what we already had,'' says Jerry Mander, a former advertising executive now with Public Interest Media in San Francisco.
For many years, this genius seemed the Merlin of prosperity and growth. But as America enters the 1990s, the grimmer implications have become harder to avoid. Debt, trash, obesity, environmental decay - these and other problems have their root in part in an incessant desire to consume.
Yet as the problems grow, so do the inducements to yet more consumption, with few words permitted on the other side. ``The problem with competition and marketing is that it is all competition for consumption,'' says Michael Pertschuk, former head of the Federal Trade Commission. ``None is competition for nonconsumption.''
Some of the implications are subtle. ``Everywhere one turns, the market economy is crying out for the nonmarket economy it has destroyed,'' observes attorney Edgar Cahn, who has developed a new system of service-barter to try to counter this trend. ``McDonalds now provides the meals, KinderCare the child care, videotapes the entertainment.'' In other words, the shifting of many aspects of life into the market arena has, in the view of some, weakened family and community life in the face of such problems as drugs and crime.
For another thing, the incessant touting of consumption means America is constantly reinventing poverty, digging a deeper hole even as it tries to pull people out. Even the well-off can feel strapped, trying to pay for needs - from VCRs to answering machines - that keep coming on-line. If high-definition televisions (HDTV) ever hit the stores, Americans will feel $2,500 poorer overnight, and will have that much less to spare for those in real need.
People try to keep up by borrowing. Personal debts doubled in the United States between 1981 and 1987 alone from $300 billion to $600 billion. Not coincidentally, personal bankruptcies doubled as well, observes Elizabeth Warren of the University of Pennsylvania Law School in a new book, ``As We Forgive Our Debtors.''
This was a remarkable chapter in economic history, Ms. Warren says. Bankruptcy and debt have generally occurred in hard times. Now they were growing in times of plenty, and the end was not in sight.
At a Manhattan car dealership last month, a salesman was explaining to Asian immigrants the magic of the American marketplace. ``You don't need money to buy a car,'' he exclaimed. ``You need credit.''
Get credit. Produce trash. Yet as the garbage heaps grow, so does the advertising messages that spawn them. Not accidentally, the three top brand advertisers - McDonalds, Burger King, and Budweiser - are also prominent producers of trash. Ad executives even resort to the language of the trash crisis to describe the proliferation of ad messages. ``How are advertisers and agencies attempting to solve the problem created by clutter,'' Rod Miller, a Utah ad executive, asked. ``By creating more clutter.''
Rarely have contending elements been so starkly poised. On one side is a growing awareness that Americans need something they have lacked for over four decades: a concept of ``enough.'' And on the other side is a business culture that just does not want to let go.
``The purpose of advertising is to stimulate excess usage of anything,'' an executive of the N. W. Ayer advertising agency said a few years ago. Today, these stimulants are everywhere. In elevators. On golf carts and shopping carts. Floating on pontoons at the beach. Issuing forth from video screens at the ballpark. Tacked onto movies at the theater.
In the movies themselves. Phillip Morris, for example, paid $350,000 for Lark cigarettes to appear in the latest James Bond movie. Book agents began talking about ``placing'' products in novels in similar fashion; Whittle Communications was already selling ad space in books.
Children's television shows became ads for ``action figures'' such as Gobots, while Courvoisier cognac and 24 other companies paid $30,000 each to appear on a board game. Whittle is launching a new cable channel - Channel One - to send advertising-laden shows directly into school classrooms.
The boldest and most pervasive move to commercialize mental space was the Walkman personal radio. These tiny units, now selling at the rate of 23 million a year, do for the rest of waking experience what television did to the home: open it to advertisers and the entertainment industry.
Choices multiply along with the messages. Car buyers now face 572 different models, up almost 50 percent from 1980. Not surprisingly, ``stress'' became the new affliction of the affluent (spawning more consumption for ``stress management'' advice). Polls show people are becoming weary of all the shopping, so companies summon the behavioral engineers to restore an upbeat buying mood. The design chief at Bloomingdales and Jordan Marsh Company said the aim of store lighting was to ``help set that stage and manipulate the consumer through the environment.''
Those who try to address these issues face the proverbial uphill battle. The media are supported by sponsors whose aim is to sell, and beyond such vested interest is an ideology of consumption that extends throughout American life. Economists, for example, still measure the national well-being according to Gross National Product, so that the more we consume, the better we think we are doing.
The scourge of divorce, for example, means more lawyers fees, more vacuum cleaners (one household becomes two) - more consumption.
Still, there are signs of resistance to the consumption ethos. Localities across the US are putting restrictions on one form of advertising clutter - billboards. A Wall Street Journal poll finds a majority of Americans favor bans on alcohol and tobacco.
Recycling laws, such as so-called bottle bills, suggest the seeds of revival of the traditional value of thrift. But many think America has to discourage so much consumption in the first place.
``It is something people haven't stopped talking about,'' says Mr. Mander, speaking of efforts along this line that halted during the Reagan years. ``You are going to see it again.''
If so, Americans may be treated to a form of discourse as verboten here as political debate once was in Prague. Mr. Pertschuk provides a sample radio spot:
``Got a headache? Go upstairs. Lie down. Take a short nap. Most headaches depart without any medication.''