What happened?!

I did this workout on Friday, as part of the Old School Challenge. It's in a few of my programs as well, it's a favorite!


However, what on earth is it in this particular workout that leaves me sore for days after? I'm talking, hard to sit and walk sore! This time I couldn't walk...it's crazy! Here it is Monday, and I'm needing to adjust my workout to allow my days another recovery day!

Anybody else experience this?