Fast-Forwarding Into Better Shape : The right videotape can help you tone your body, make you stronger and improve your cardiovascular system, experts say. But they warn that you have to choose one carefully.

You may not remember it now, but back around New Year’s Day you probably made a resolution to snap your body back into shape. However, as the months have passed by, that promise has been forgotten just like the score in the Rose Bowl.

But while your waistline, which tends to have a long memory, is still there, and the revealing clothing of summer is already hanging on department store racks, it’s not too late to attack the flab with the help of video technology.

Exercise videos have been around since the VCR became a popular household acronym, and are a popular and private way to shape up.

Working out to an exercise tape can tone your body, make you stronger and improve your cardiovascular system, say experts. But it can also cause you to lose interest in exercise, or, even worse, hurt your legs and arms. Before buying an exercise tape, examine your present exercise habits.

“Exercising to a video is great, as long as you can stick with it,” says Janet Konecne, director of physical therapy at Sports Rehabilitation Center in Anaheim. “But some people have a hard time unless they have a lot of self-motivation.

“They’ll get the video and work out for a few weeks, then the monotony will set in and they’ll put the tape on the shelf. That’s one of the advantages of exercising with other people. You tend to make friends and develop a social obligation to go each time.”

Also, check with your doctor to see how much and what type of exercise is right for you.

“You’ll want to find out what’s safe for your body, and whether you can attain the look you want by yourself,” says Konecne. “A lot of people aren’t in the kind of shape needed to do strenuous exercises.”

With nearly 500 titles available, picking an exercise video that will help you reach your goals isn’t easy.

There are four basic categories of exercise tapes, each aimed at helping you achieve your specific goal:

* Aerobics tapes condition the cardiovascular system and help you burn off calories.

* Toning tapes work on specific parts of your body, improving the look of your stomach, legs or arms.

* Combination tapes provide both aerobic and toning exercises.

* Specialty tapes cover areas such as meditation, yoga and stretching.

“You may have to weed through a lot of tapes before you find a good one,” says Judith Ray, a physical therapist with Hoag Hospital in Newport Beach. “It’s best if you can rent the video before buying it and watch it all the way through to see how the routines are done.

“There are so many celebrities with videos, I think it’s important to look at the credits to see if the tape was made with the advice of a physical therapist or athletic trainer.”

Ray also points out that the more fitness expertise the host of the tape has, the better it usually is. “People like Kathy Smith or Jane Fonda have produced tapes with safe, sound exercise principles. But just because someone is famous doesn’t mean their tape is good.”

A good tape has an introduction that discusses the type of shoes and any equipment you might need. It will also have a 10- to 15-minute warm-up period, an exercise period of at least 20 minutes and a short cool-down period.

When inspecting or viewing an exercise tape, see if it stresses low- or no-impact aerobics. If you see the presenter jumping up and down for most of the exercise, you might want to try another tape.

“High-impact aerobics, where your feet hit the ground hard, put a great deal of impact on your spine and legs,” says Barbara King-Latronica of the La Palma Physical Therapy and Sports Medicine Corporation. “Most people have back pain at some point in their lives anyway, so why increase the risk by doing high-impact aerobics?”

A good tape should also work your arms below the level of the shoulders, since this puts less stress on the heart. “People also get shoulder pain when they work their arms above the shoulders because they’re not used to exercises like that,” says King-Latronica. “And the first rule of exercise is: If it hurts, or you don’t think it’s right for your body, don’t do it.”

If the tape you’re interested in is a few years old, check to see if there’s an updated version, since fitness philosophies have changed in a relatively short period of time, says Ray.

“Jane Fonda’s first workout tape had some hard movements and poor body mechanics, but in later editions the exercises have improved, and I’ve found that most newer videos emphasize less jarring, low-impact aerobics, where one foot remains on the ground at all times,” she say. “It’s less active, but you’re still getting your heart rate up, which is your objective.”

A good exercise video should also show more than one level, so you can progress as your fitness improves. “This will help keep up your interest and keep you challenged,” says Ray. “You’ll also want to see if they mention monitoring your heart beat.”

There are many exercise videos that feature new or unusual twists. The Dancing Grannies are a group of senior citizens from Arizona who’ve produced aerobic exercise tapes designed for the elderly. “The Grannies tapes also show a number of people exercising,” says Konecne. “This creates the feeling that you’re with a group.”

Another trend is in step aerobic tapes, which have the viewer exercise by moving up and down on a small step. The step only has to be four to six inches high, and step workouts work leg muscles efficiently in addition to increasing the heart rate.

For those who want to return to their past, there are jump-rope videos that show how you can increase your fitness and agility.

If you dread the boredom of an exercise bicycle, there are tapes that can take you far from your living room.

“At our center, we have a popular tape for people riding the bicycles called ‘Bike Riding Through Maui,’ ” says Konecne. “As you’re exercising, you watch the screen and you’re shown a bicyclist’s view of some of the scenic trails on the island. Plus, there are cues in it where you’re asked to check your heart rate.”

You might also look at dance tapes where the instructor emphasizes safe aerobic activity along with the fun of dancing. “There’s a video by Rita Moreno that provides an excellent workout,” says Kathy Corcoran of New Energy Dance Studio in Yorba Linda. “She teaches simple dance moves along with no-impact aerobics. It shows nothing that would be threatening to the body.”

Even if you don’t wind up exercising to a tape, a quick look at what’s available would at least soothe your conscience. “Looking at all the tapes reminds me of what I’ve got to do,” says Maryanne Rowley of Huntington Beach, as she walked out of a video store after renting an exercise tape. “It’s better to start now than never.”