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I have been squatting 2-3 times per week for a few months now usually warming up and then doing 3x5. I have been making some decent progress and I thought everything was all well until a friend of mine commented on a set of mine today. He claimed that my lower back was rounding right when I almost got to parallel. The gym that I go to has a mirror infront of the squat rack but not to the side. I set up with my shoulders back and such so I thought I was keeping a neutral spine and although I would sometimes get pain in my lower back for a few seconds after some sets I thought nothing of it as it went away after a few seconds and I felt fine the next day. I then reracked the weight turned sideways and attempted to do a bodyweight squat. He was right, withing about 20 degrees (guess) of parallel my lower back rounds and if i go slow and try to forefully keep it from rounding it streches my hamstrings and basically is almost impossible for me to do it. I have read other places that tight hamstring can cause this and I for one have those as I am lucky to get my hands within a foot and a half of the ground when doing the classic bend over hamstring stretch. My dad is similarly inflexible, but I have never worried about it as it really never bothered me through high school running/soccer and I have been active my entire life. This now worries me though as I really don't want to stop squatting as it is a great exercise and it helps me make gains on all my other lifts. FWIW my hamstrings give me trouble on deadlifts but I can still complete them with proper form although I feel that I could lift heavier with more flexibility. Basically is my assessment correct? If so, what are my options? One solution suggested by http://www.t-nation.com/readArticle....rmanceTraining is moving to rack pulls and front squats while working on flexibility. I realy don't want to have to stop doing these as I truly like the burn/sense of accomplishment/exhaustion they give and I have made more gains in the last 1.5 months doing deadlifts/squats then in the prior 4.5 months without them.