Slothful fantasy: Workout in a pill

Scientists have discovered what could be the ultimate workout for couch potatoes: exercise in a pill.

In experiments on mice that did no exercise, the chemical compound, known as AICAR, allowed them to run 44 percent farther on a treadmill than those that did not receive the drug.

“We have exercise in a pill,” said Ron Evans, an author of a study published Thursday. “With no exercise, you can take a drug and chemically mimic it.”

The drug, according to the researchers, changed the physical composition of muscle, essentially transforming the tissue from sugar-burning fast-twitch fibers to fat-burning slow-twitch ones – the same change that occurs in distance runners and cyclists through training.

The researchers said the drug's fat-burning ability could also help reduce weight, ward off diabetes and prevent heart disease – the benefits of daily aerobic activity without the perspiration.

“It's an amazing piece of pharmacology,” said David Mangelsdorf, a pharmacologist at University of Texas Southwestern Medical Center in Dallas who was not connected with the research. “You're getting the benefits of exercise without having to do any work.”

It is unknown if the drug has any benefit for athletes who actually work out – or any human for that matter, since the research has so far only involved mice.

Evans, a molecular physiologist at the Salk Institute for Biological Studies in the San Diego community of La Jolla, said he has already been contacted by dozens of athletes and overweight people who have heard about his research from several lectures he has given on the subject.

Evans said he has notified world anti-doping officials, who are now scrambling to implement a test for it before the Beijing Olympics start next week.

The compound, which is naturally produced in tiny amounts in human muscle cells and has been studied for decades, is readily available through Web sites that cater to researchers. One site was offering it for $120 a gram.

Evans predicted that in the wake of his study, published in the journal Cell, it will “fly off the shelves.”

With more research, he said, the drug might one day be used as a treatment for muscle wasting, obesity, and as a means of allowing bedridden patients to reap the benefits of exercise.

The drug has been tested in humans for a variety of conditions related to the heart and repeatedly passed basic safety tests.

“It was found to be a quite safe drug, at least at the doses we were using,” said chemist Paul Laikind, who patented the compound in the 1980s and began testing it as a means of preserving blood flow to the heart during surgery.

The Associated Press contributed.