The most popular workout machine in the U.S. is now available with more bells and whistles than ever before.

More Americans regularly work out on a treadmill than on any other type of exercise machine. The total was 11.6 million in 2003, the latest year for which figures were available, according to the Sporting Goods Manufacturers Association. Our readers, too, favor treadmills over other equipment, according to our latest Annual Questionnaire.

The effort to make exercise interesting and as pain-free as possible has led to an array of features. One useful device found on most tested treadmills was electronic programming that automatically increases or decreases the workout's intensity, the way running up and down real hills does outdoors. You can also make the adjustments manually. On the gimmicky side, a growing number of treadmills load the console with gadgets such as fans, a CD player, a cubbyhole for a TV remote, and backlighting on the display that for some may evoke a digital watch.

The disappointing news from our most recent tests is that a number of machines had problems such as mechanical failures that seriously affected performance. We've found in recent treadmill tests that you have to spend well over $2,000 to get a machine designed for serious runners, though lower-priced models are OK for walkers.

WHAT'S AVAILABLE

Icon Fitness offers a range of lower- and midpriced treadmills sold under the Image, Nordic Track, Proform, Reebok, and Weslo brands. You'll find those brands in Sears, The Sports Authority, Wal-Mart, and other national sporting-goods chains. Moderately priced brands, such as Horizon Fitness, Schwinn, Trimline, and Vision Fitness, as well as pricier brands, such as Landice, Life Fitness, Nautilus, Precor, and True are sold in specialty sporting-goods stores. You can also buy many treadmills online.

Treadmills fall into three basic price categories:

Basic treadmills are fine for strictly walking and typically include a 10-mph top speed; a 10 percent maximum incline; a display for speed, distance, time, and calories; a shelf and water-bottle holders; and a folding deck.

Price range: $300 to $700.

Midrange treadmills have superior construction to basic models, making them better suited for walking and occasional running. They include the same features as basic treadmills, plus a heart-rate monitor and exercise programs.

Price range: $800 to $1,800.

High-end treadmills are best for frequent running and typically have the same features as midrange machines, plus a sturdier deck and frame, and a more powerful motor for frequent long, fast running. Most lack a folding deck, however.

Price range: $2,000 to $3,500.

FEATURES THAT COUNT

Look for well-labeled controls that are laid out intuitively. Also look for up/down buttons to control speed, which are easier than sliding switches. And while most treadmills now have a heart-rate monitor, models that use a chest strap tend to be more accurate and convenient than those with a handgrip or thumb-sensor monitor. We also like large, easy-to-read displays that show multiple functions, such as time, speed, heart rate, and incline, at once.

Most treadmills have handles or rails in front and on the sides for those who may need added security. Padding is a plus. Handrails shouldn't get in the way of your arms while exercising. In addition, the motor housing should be relatively flush with the front of the belt or concave and set forward far enough so it's away from your feet. Ample foot rails that are wide and flat on either side of the moving belt make getting on and off safer and easier.

If you're running, a belt at least 18 inches wide by 50 inches long is best. And if your exercise room is small, you'll appreciate a folding deck, which frees up roughly 6 square feet compared with non-folding versions.

On most models, a tethered safety key is needed to start the treadmill. It also stops the treadmill when pulled out, either at the end of your workout or if you should fall. Models that work without the key pose a possible concern for those with young children.

Varied exercise programs, available on most models, are a possible antidote to boredom.

Also check the warranty. Better warranties offer lifetime coverage on the frame, at least three years on the motor and one-year labor coverage. Consider an extended warranty for treadmills with less coverage.

HOW TO CHOOSE

First decide whether you want to devote the money and space to a big exercise machine. A living-room workout is the height of convenience, but of course, you can get fit exercising outdoors or at a gym. If you decide to buy a treadmill, consider these tips:

Try it out first. Every model is a little different, so you shouldn't buy one before using it in the store.

Decide which features you'll use. Some, such as exercise programs, can make a workout more varied and less boring, which may get you on the machine more often. But don't pay for frills you don't care about.

Consider your space. Nonfolding treadmills take up as much floor space as a couch. If your workout room does double duty, a folding treadmill can save you about 6 square feet.

Consider your workout intensity. If you'll usually walk rather than run, any of the tested models will suffice. Decide based on your budget and the features you want. If you run, construction quality is paramount.

Copyright © 2003-2008 Consumers Union of U.S., Inc.

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