Hope for the Sedentary: Too Good to be True: The Four-Minute Workout Machine

I work hard at staying fit, but that doesn't mean I enjoy it. Running for half an hour or more five or six days a week is just the price I grudgingly pay in time and discomfort to stay healthy.

So when I heard about a machine that promised a full aerobic and strength-training workout in just four minutes a day, I had to check it out. The device, called the ROM (for Range of Motion) 4-Minute CrossTrainer, is a futuristic-looking contraption with an impressive price tag ($14,615). The manufacturer's website offers a scattering of testimonials (Tom Cruise reportedly owns one) and a link to several scientific studies backing up the four-minute claim.

Fortunately, I didn't have to come up with $14,615 to give the machine a whirl. A doctor in my hometown has opened a one-ROM fitness center that he was kind enough to let me use. The device has two stations, one at each end. The first is like a rowing machine, except you have to push as well as pull; the second is like a stair climber. After four minutes on each, my heart was pounding, my muscles felt like lead, and I thought I was going to faint. I had certainly got a workout.

But was it really equal to a full session of aerobic exercise? I had Miriam Nelson, a respected exercise physiologist at Tufts University, look at the three studies cited on the website. What they actually say, she explains, is that adding an intense four-minute workout to your regular aerobic routine can make you slightly fitter. Beyond that, the studies were small and 10 years old. If the four-minute workout truly worked, Nelson says, "everything we know about fitness and metabolism would be wrong. I just don't buy it." Oh, well. I guess I'll just go running. --By Michael D. Lemonick