How do I switch back from the crown level system to the memory bar system?

I clicked on the pop up to update and try the new crown level system, which instead of the memory bar that was before that would go down over time, this one shows you crowns and the more you practice an excercise, the more crowns you have. I don't like it and I'd like to go back, but I don't know how.

March 22, 2018

March 23, 2018

Here's how if you're on Android:

April 10, 2018
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