"Strangers on a Treadmill" is the fourth episode of the second season of the American sitcom, Modern Family and the 28th episode of the series overall. The episode originally aired on October 13, 2010 on American Broadcasting Company (ABC). The episode was written by Danny Zuker and directed by Scott Ellis.

In the episode, Claire and Mitchell try to spare their significant others from embarrassment, Haley tries to teach Alex how to be cool while Jay tries to prove to Gloria that he knows his employees' names.

"Strangers on a Treadmill" received mostly positive reviews with Joel Keller saying the secondary plots "didn't quite make it", but had "fun moments". According to the Nielsen Media Research it received a 4.8 rating/13% share in the 18–49 demographic increasing 4% from the previous episode. The episode also became the first of the series to become the highest-rated scripted program of the week in the 18–49 demographic.

The episode begins with Phil (Ty Burrell) writing jokes for the SCARB (Southern California Annual Realtors Banquet) that he is hosting. Unlike what he thinks, Claire (Julie Bowen) believes he is going to bomb with his unfunny jokes.

Cameron (Eric Stonestreet) decides to work out with bike shorts much to Mitchell's (Jesse Tyler Ferguson) chagrin. While working out, Claire and Mitchell decide to tell the others' spouse of their bad habit (like Strangers on a Train). At the Dunphys' house Mitchell arrives to tell Phil about his bad jokes. Unfortunately Mitchell can not go through with it after seeing Phil's sad face. Meanwhile Claire tells Cameron about how bad he looks in bike shorts causing Cameron to go and cry in the hallway.

Later that day Claire calls Mitchell asking him why he did not go through with their deal. While they are talking, Cameron hears the conversation and becomes sad once again. To prove their relationship can stand anything, Mitchell gets ready to cut off his beard, but after only cutting a single part of it, Cameron tells him he loves his beard. The couple kiss and make up, but they soon get into another disagreement.

...
Wikipedia