After reading Eric Cressey's latest article at T-Nation, I decided to scroll through the questions and see what people wanted more information about. As always, there's a guy on there purporting the benefits of loaded spinal flexion training (i.e. round back deads, stiff-leg deads, etc.)
Now, before people flake out on me, understand that I'm a realist here. I understand that spinal flexion does occur at some points in time. On a maximal deadlift, there might be some loss of your arch, neutral spine, or even a slight movement into flexion. This isn't the goal though! I believe the research clear states that elite level powerlifters kinesteically know and understand to stay out of end-range flexion (the last 2-3 degrees).
So why, when leading researchers and even coaches tell you to stay out of loaded flexion, do some people continue to purport it? I'd imagine the key here is that they've probably never been injured before. I've often met people who claim to have a "strong back" and they get away with all the no-no's of lifting.
My question then becomes, so what happens when you DO get injured? Did your back all of a sudden become weak?
Whether it's an acute thing or something more chronic, I'm not willing to take that risk with my body. After all, poor strength training may not catch up to you for years - but when it does I'd imagine you'll wish you had trained a little bit smarter.