For the past month or so, with the help of some of the great articles here, i have been doing squats where i drop down a little below parallel. I use to always do half ass squats and never saw much progress. I'm a tall guy so it was hard for me to get low. After going down lower i have noticed my muscles seem to be working a lot harder. I have added about an inch and a half around my thighs in the last month or two.
My question is, for the past week when i get down low and go back up there is some pain in what seems to be my lower back on the right side. It feels like it is below my waist line and maybe an erector spinae muscle or near the pelvis. From what i can tell i have good form and my back stays straight. I do some dynamic stretching before i work out and static afterwards. Any tips on what i can do so there isn't some pain in that area? I don't want to stop doing these because i feel like i've made progress doing them.
Also, there was some lady watching me done them today and stopped to tell me that i shouldn't go below parallel because i will blow out my knees. This is what she heard from other people or trainers. I told her i do it because i feel like there is more muscle recruitment and muscle fiber recruitment, plus it doesn't hurt my knees.
After i finished i watched her do some squats and she only went down about a quarter of the way. I didn't feel like arguing with her and just dismissed what she said. It's funny how some people at the gym try to correct you and they can't even do it right.