It's not every day you see Arnold Schwarzenegger on Reddit!
He's got this thing going called Arnold's 1% Challenge, where he asks people to commit 1% of their day (15 minutes) to doing some cardio. And as part of it, Dr Layne Norton penned an article which he calls 'Best Damn Cardio Humanly Possible in 15 Minutes.' It was posted on Reddit/r/Fitness and, sure enough, people started arguing about whether the routine was any good.
So, after listening to enough bickering, Arnold decided he'd had enough and stepped in to give everyone a telling-off.
You tell'em Arnie!
Hat-tip: Bobby Big Wheel