Exercise in a Pill?

Scientists have identified a protein enzyme that mimics the effects of aerobic exercise on skeletal muscle. As reported in the April 12, 2002, edition of Science, a research team found that muscle in mice engineered to have an overactive form of the enzyme calmodulin-dependent protein kinase, or CaMK, easily transformed so-called fast-twitch muscle fibers, which tire easily, to fatigue-resistant slow-twitch muscle fibers of the sort found in marathon runners and others who participate in endurance sports.

Although decades away?and definitely not intended for the couch potatoes among us?the ultimate result may be drugs to help people with conditions such as congestive heart failure who find exercising extremely difficult.