The first time I see a jogger smiling, I’ll consider it.

In this quip, Rivers uses observational humor to puncture the moral earnestness often attached to exercise culture. The line implies that jogging is so unpleasant that genuine enjoyment would be rare; until she sees proof—an authentically smiling jogger—she won’t be persuaded to join in. The joke also plays on Rivers’s comic persona: skeptical of self-improvement fads and quick to expose the gap between public virtue-signaling and private experience. More broadly, it’s a one-liner about evidence and persuasion: she frames her resistance as rational (“I’ll consider it”) while setting a deliberately unlikely condition.