Hey guys just wanted to see what pointers you all have for my Jefferson Curl Form. I noticed that on the first couple reps I get kind of a pain right in my tail bone area but it seems to go away if i focus on straightening my legs / internally rotating my hips. Should I only be going as far as my spinal flexion allows? Or is it okay to continue down with my lumbar in one chunk like in the video so that I still get a hamstring stretch?