Houston Chronicle: Yoga Challenge

They're all over social media: Down-dogs on Instagram. Facebook Live videos of a steadily growing daily number of pushups. Snapchats of barbell snatches at Crossfit.

But what do participants really get from making a daily commitment to post their progress online, along with thousands of strangers? And is it worth it?

"People get stronger. They're able to do things they couldn't do a week ago," says Nathan Herrington, head of team development at Big Power Yoga, which regularly hosts yoga challenges that encourage participants to attend class six days a week.

The benefits are more than skin deep, though.