If you missed the PTDC posts this past week here they are:

So you want to make and market fitness equipment? - Jon Goodman with help from Josh Henkin, Ken Zelez, Marc Lebert, and Anthony Carey

Personal trainers shouldn't periodize - Jon Goodman

Here are the best posts from online personal trainers

Box squats vs squats to a box (yes there's a difference) - Tony Gentilcore

Are you making This critical corrective exercise mistake? - Coach Nick Tumminello

Break up those hips and fix that squat - Adam Vogel (on T-Nation)

Two deep squatting tips and my 20-rep squatting experiment - Anthony Mychal

The cause of obesity part 1and part 2 The cause of obesity part 2 - Anoop Balachandran

Occupy muscle beach - Lou Schuler

The incredible and unaging triathlete - Alex Hutchinson (this is wild)