A Toronto company is offeringa mini-workoutfor the time-starved office dweller and saysthe benefits are comparable to those of amuch longer exercise routine.

The company, H.I.T Fitness, says just four minutes on its $15,000 range-of-motion machine is equivalent to about 45 minutes of resistance training, 30 minutes of running and 20 minutes of stretching.

Fitness experts not associated with the firmare voicing skeptical opinions.

"I find it extremely hard to believe the claims, without empirical evidence," says Sheldon Persad, a strength and conditioning coach with the Canadian Sports Centre - Ontario.

"They offer a [research] paper on the website, which isn't a research paper at all. For me to take their claims seriously I would have to see more than one published paper, in a peer-reviewed journal."

Jack Goodman, a professor of physical education and health at the University of Toronto, also says he's not buying into claims about the four-minute workout, adding there's noquick fix to physical fitness.

Burns calories over 24 hours: company

Julie O'Brien, director of operations at the company, says the workout burns just 40 to 50 calories, but the resulting "afterburn" will eat up another 500 calories over24 hours.

Fitness buffs strap themselves into a 204-kilogram machine with twoparts: the front workslike a rowing machine, while the back has anelliptical step apparatus.

Persad says it sounds like a"fairly high-intensity" routine and he's concerned how a neophyte would handle it, but O'Briensays there are 20 different levels.

"My initial reaction was 'no way,'" O'Brien says. "But you're using all of your muscles at once in a continuous range of motion, and the resistance changes from second to second."

The first exercise shop featuring the four-minute workout on one ofsixcross trainersis operatingin the underground shopping pathwaybeneath Toronto's financial district.

"We're the only gym in Canada to have this," O'Brien says.

The company is planning to open two other locations in the Toronto area soon and is hopingto have 40 to 50 locations within five years.

The American College of Sports Medicine (ACSM) saysfor improvement of cardiovascular fitness and body composition, itrecommends adults performphysical activity involving the large muscle groups, three to five times each week, for 20 to 60 minutes at a time.

Studies using the range-of-motion machineshow improvement in cardiovascular fitness, measured by VO2 (oxygen uptake),occur within six weeks, the company says.