Feeling blabby? Maybe you'd like to head for the health club and lift some weights, but you can't stand the thought of walking in and finding a bunch of beefy, sweaty buddies standing around showing off their bulging, glistening muscles. The makers of home gyms know you're out there. Weightlifting may be the only sport that's come out of the closet only to go back in --usually to the basement or the rec room as both men and women begin to realize that weight training is an excellent all-around cardiovascular workout and also tones and strengthens muscles.

One of the most popular home fitness gyms to reach the market is the simple rowing machine, a device that sits horizontally on the floor and does just what you'd expect: it works the shoulders, back, legs and cardiovascular system. "We recommend the rowing motion as a warm-up and warm-down," said Ken Earle, manager of operations at Fitness Industries in Rockville. "Right now, the rowing machine is very popular. We sell them as soon as we can get them."

Diversified Products manufactures the DP Bodytone 300, a rowing machine that can also be used for bench-pressing, shoulder-pressing, squats, overhead pulls and curls. The hydraulic cylinders are easily adjustable to give a wide range of resistance and positions. The rowing machine is easily stored, and at $150 it is one of the least expensive ways to exercise. Two other popular rowing machines are the Club Tunturi ($250) and the 610 Deluxe Rower ($280), produced by Amerec.

Fitness Industries, which manufactures equipment and operates a weight-lifting club, has introduced a bench that connects to the Club Tunturi and converts it to a complete and compact home gym. It costs an additional $125. "Up to now, people have been rowing for fitness," said Earle. "If you're creative, you can do dozens of different exercises with the bench. The bench is the icing on the cake."

For those athletes who desire a more complicated fitness machine, choices vary widely in price, size, portability and technology. The Diversified Products Gympac Series easily mounts to a wall and requires only 32 square feet of space. The Gympac ($300) exercises every muscle group through progressive weight resistance, and provides incremental weight selection from 22 to 110 pounds. It comes complete with weights, a bench/slant board, handlebar, leg lift, double-handle pulley assembly, pulley bar and ankle straps, for 61 different exercises.

The essence of the Solorflex fitness system (whose ads flaunt a stomach as hard as the rock of Gibraltar) is a rubber band, which is attached to a bench press. The bands have different tensions, so the load is adjustable. The Solorflex system ($500) is portable and requires about three square feet.

The design behind the Total Gym by Westbend has been used for more than nine years by physical therapists, but it reached the mass market only two years ago. With the Total Gym, your own body weight and gravity provide resistance as you pull yourself on a "sled" up and down a slant board. article was about bicycle rollers. reater the resistance. Your weight on the sled becomes the workload. Larry Johnson, a salesman for Herman's sporting goods, recommends the Total Gym ($350) for beginners who are interested in all-around fitness, including muscle toning, endurance, strength and power through isolated exercises.

Herman's also sells the Marcy Body Bar, which works on a pulley system. This popular unit ($350) consists of a vertical rack of weights--100 pounds divided into 10-pound increments. Also included is a workout bench/leg developer that attaches to the rack for bench presses and other exercises. The Body Bar must be bolted into a wall; or you can buy the Freestander ($160) to support it.

American Physical Fitness, a manufacturer and retailer of fitness equipment, produces and sells fitness units, rowing machines, and exercise bicycles that range in versatility and detail as much as in price. For example, APF offers the Chrome Cal Masterline 500 Series for $1,295 (including delivery and set-up). This elaborate home gym uses a conventional bench press with 200 pounds of weights and a quadriceps/hamstring curl attachment at the end of the bench. A bar on the top of the unit can be used for straight arm presses.

Home gyms offer privacy, but this seclusion can be a drawback. Since only one person can work out at a time, the machines sometimes are fuel for family squabbles. And exercising alone can be boring--and sometimes dangerous. Most machines, however, have a built-in safeguard: since the weights are not "free," that is, since they are securely attached to the home gym, there is little chance of injury from a weight falling.

Nothing in the home gym, however, can keep an exerciser from misusing the equipment and pulling a muscle--or worse. Although most gyms come with complete instruction books, you should still exercise with caution in your own home.

A final note of warning: before you select your home workout center remember that some machines have to be installed--bolted onto the wall. If you don't want to wreck havoc in your rec room, or if you're not handy with a drill, look around for a free-standing unit.