1. You learn pretty quickly how hard you can work out in ‘just’ 28 minutes. “It’s only 7 minutes per circuit,” said no one ever.
2. You completely understand why the app’s called Sweat With Kayla. Spoiler alert: you sweat a lot.
3. When you spy someone in the gym using a printed guide, you instantly become BFFs. And you’ve definitely spent a good 10 minutes trying to work out if the girl in front of you is using the app or just playing with filters on Snapchat.