Personally, I spend zero time training lower back, or programming it for clients. In 20 years, I have yet to meet a client who needed additional low back strength. People tend to have limited hip and thoracic spine mobility, leaving the low back muscles to translate force between the hips and torso, generally causing strain or worse.
I spend a great deal of time working on mobilizing those joints that are supposed to be mobile – ankles, hips, t-spine, shoulders – and working on the muscles that stabilize the joints that are designed to be stable – knees, lumbar spine, scapulae.
Since the low back muscles typically handle more load that they are meant to, they are tighter than the ideal, and in a state of constant extension. My clients spend lots of time performing anti-extension exercises, variations of planks, etc., to begin to bring their lumbar posture back toward neutral.
Hope that’s helpful!
I believe Andrew has a great point in regards to working the lower back! It gets an enormous amount of indirect influence through the use of numerous movements.
Many of those who experience lower back pain come from a direct result of poor posture or weaker muscles such as the glutes and tighter muscles in areas such as the hamstrings or psoas.
I find that “activating” my clients key areas (glutes & scapula) along with increasing the mobility of the spine and hips tends to correct the positioning of the body and protect the body and greatly reduce or even eliminate pain.
As far as the answer to abs I usually assess that as to what my clients goals are and then take a look at their genetics. If they have small abs muscle bellies and want a six pack popping out I may add heavier resistance. If they are looking to improve the quality of life I would throw more plank-type movements and teach them how to “rock the boat” and build true core strength.
Great question Jill!