TL;DR
Exercise in a pill has left the mouse cage. Two drugs built to copy part of what a workout does to the body have now been given to people. One was safe in 88 adults and did nothing measurable yet. The other, by its maker's account, added about 1.8 pounds of lean muscle and stripped about 2.4 pounds of fat in eight weeks, in just 13 people with no comparison group. Neither is proof. Meanwhile the best-known mouse compound is already sold online and drug testers can already catch it. For people who cannot exercise, such as the very old, the sick, or those losing muscle on weight-loss drugs, a pill that copies even one slice of a workout could matter. For everyone else, nothing on the market beats lifting weights and sleeping enough.
Below the line, for paid subscribers: The full story: where it stands, how we got here and what's dated next; our Odds board on 6 milestones, starting with "Enveda starts a Phase 2 trial of ENV-308 by 2027"; our labeled speculation on what it adds up to; and every source.