Sorry, just to be clear.

Everyone stands around in a circle and one person drops down on the floor in a plank to talk? Maybe it's just me but I'd have a hard time taking this seriously.

This isn't a thing. It may have happened, especially if it's some fitness startup or something, but this seems like just a piece of outrage bait.

It’s not just you.

That sounds like a practice suitable for 13 year old boys, not professionals.

I did search twitter and found 3-5 year olds!

https://twitter.com/search?f=images&vertical=default&q=push%...

Actually I found a more recent tweet depicting the actual practice, which has since been deleted. For the record, it was the same photo that appears in https://medium.com/@william.liu/daily-plank-meeting-732456e6... , a post that advises (!) this practice.

Not physically fit OR disabled OR actually dressed for an office environment, not a gym (last one is especially relevant for females).

> Obviously disadvantages people who aren’t physically fit as they literally don’t get to contribute as much!

If I am quiet in a meeting when I have a contribution to make--and make no mistake, I'm not speaking up regardless of my fitness level--my employer suffers, not me. He suffers again when his messed up culture inevitably causes me to find another employer.

What does "plank" mean in this situation? Dict doesn't seem to help.

It's a sort of exercise where you hold yourself in a position as though you're going to do a push up, so supporting your body weight on your feet and either hands or your forearms while suspending your body a few inches off the floor. The aim is to just hold this position for as long as you can, normally.

See: https://en.wikipedia.org/wiki/Plank_(exercise)

Good core exercise, probably inappropriate for meetings.

The plank exercise is very similar to a pushup exercise move. It comes from making your body straight as a board (plank of wood). The position is face-down on the ground, with all of your weight supported by your toes and forearms.

It is generally difficult to hold that position in proper form for long periods of time (or at least your muscles start to ache)