Exercise in a Pill? Researchers Face New Challenges, Advancements

In the search for a pill that could replace exercise, researchers have published two new studies examining just how such a thing would work, and whether or not it would actually be a good thing.

One of those studies, conducted by researchers at the Scripps Research Institute and published in the journal Nature Medicine, builds upon a study published last year in Nature in which scientists reported that a compound injected into obese mice increased activation of the protein called REV-ERB.

As this happened, animals lost weight, even on a high-fat diet, and began using more oxygen throughout the day and expending more energy, even though many of them did not move more than their peers - in fact, some of them were downright lazy.

In effect, the mice appeared to be experiencing a workout simply by going about their daily routine.

Based on these results, the scientists joined with researchers from around the world conducted a study in order to discover what, exactly, their compound did in the muscles.

One thing they knew was it increased REV-ERB production, so they developed a strain of mice unable to express very much of the protein in their muscle cells. What the scientists found was that those mice turned out to have extremely low levels of mitochondria, a cell's energy factories.

As a result, they tired much more quickly, reaching exhaustion on treadmill testing long before untreated mice.

All of this changed, however, when the researchers added their compound to isolated muscle cells in the mice. When this happened, the cells began pumping out more REV-ERB and, as a result, began creating more and more mitochondria as well as strengthening those already present.

The scientists then injected the compound into mice that were simply sedentary. These mice responded by producing REV-ERB beyond normal levels, meaning their aerobic endurance suddenly increased.

However, a study published in PLOS Biology nearly simultaneously as the one in Nature Medicine acts as something of a warning to anyone getting their hopes up about the latter.

In it, researchers at Washington University School of Medicine attempted to replicate earlier work in which large doses of resveratrol, a chemical found abundantly in grape skins and red wine, was shown to increase production of new mitochondria, mimicking aerobic exercise.

In doing so, the scientists found that the only way to stimulate this activity was through extremely high doses of the chemical -- doses that ultimately turned out to be toxic.

Ultimately, as Dr. Thomas Burris, a co-author on the REV-ERB study, told The New York Times, the benefits of exercise are many, meaning that "no drug can" recreate all of them. Should a hypothetical exercise pill help anyone at all, it would be those suffering from illnesses and conditions that render strenuous physical activity, or any physical activity at all, extremely difficult and even impossible.