Williams and his colleagues announced that they knew why weight lifters develop more of a muscle fiber called fast twitch and long-distance runners exhibit more of one called slow twitch. The team defined a molecular pathway that directs the cells to be a particular muscle type. This pathway provides a signaling mechanism triggered by activities such as aerobic exercise. Equipped with this new knowledge, Williams is confident that they can create a drug to mimic some effects of endurance exercise. But don't settle into that easy chair and expect to never exercise again.
Exercise promotes human health.
It increases functionality, and it lowers the risk for conditions like heart disease. So if we had a pill to do that, you'd want it, but I don't think any pill will ever totally create what exercise does. Possibly, but it's never going to make them into Olympians. One important implication of this research could be to help people recover faster from an illness or trauma that makes them immobile. They need to build up their muscles so that they can restore other bodily systems.