If leg raises are bad for your lower back, there are ways to ... deadbug instead — a bodyweight abs exercise that helps strengthen your deep core muscles without weights and can easily replace ...
In fact, the Jefferson curl is more of a mobility exercise that strengthens the muscles of the lower back and core, as well as stretching the hamstrings, to help build a more resilient spine.
Plank variations also strengthen superficial and deeper muscles, and adding the twist moves your trunk through rotation, working the oblique muscles. I recommend adding a variety of exercises to ...
However, anyone with an injury or illness should exercise cautiously ... to release tension from your back and hips and strengthen your glutes, core and shoulder muscles.