What happens when you work out EVERY DAY, for 90 days? Four Buzzfeed-ers gave it a try, following the latest version of P90X —a home exercise regimen created by fitness pro Tony Horton — to complete the program’s recommended 90 straight days of high-intensity workouts. They documented their body weight and composition before and after, along with their experiences with the all-or-nothing workout regimen.

You’d think three months of intense workouts would yield muscle gains and fat loss, right? Not so fast! Watch along for the surprising results, plus whether they’d give it another shot.

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