I’ve noticed that whenever I fail to squeeze my glutes properly right before initiating the pull on deadlifts, my lower back tends to round. I’d like to know why this happens so I can understand deadlifts better - can someone explain it please?
So tensing the glutes directly can cause back rounding, but activating them by pushing through the heels is OK.
I think my problem was not pushing through the heels, which led to me not using my hips/glutes well.
Have you ever thought that your lower back may be weak. It should be locked in a tight arch. It also could be that your hips are tight and lacking mobility therefore the lack of mobility in the hips is compensated by lumbar flexion. Read some of Mike Robertson’s stuff.
I also learned to take a deep breath and fill my belly with air in order to stabilize the core.
When the glutes contract, they posteriorly tilt the pelvis, thus you are experiencing the rounding of the lower back.
With all the talk about inactive glutes, you would think you that contracting the glutes in that manner during any lift would make sense.
The key point, I think, is when you finish the lift, you are extending through the hips rather than hyper-extending your back.
You should be able to activate your glutes though, without posterior tilting your back. Think of doing “glute dances” when your sitting down. I got this from Bushy actually.