I have the feeling I’ve always had a weak back.
Some 4 months ago I started working out regularly. Now I can almost touch the floor with my hands without bending my knees.
While doing this exercise I heard a small crack on my back, nothing serious.
Since then I can lift weights easier than before but my back still hurts a bit. My back doesn’t hurt as much after coming home from work, which was normal before.
What else could I do to have a stronger back?
As others have mentioned, core exercises will be key here.
Some more traditional non-core exercises like squats and deadlifts will be engaging your core muscles (and a reminder that your ‘core’ is your whole trunk/body and not just your abs!), but you can progress this along with additional core exercises.
As someone that sits a lot for work, I really like to do ‘supermans’ and variations of them, a basic one is to lie flat on your stomach with arms and legs extended, then raise your arms and legs off the floor. You can hold, do them as reps, “swim” in the air, add in some pulls (like an overhead row if you have a resistance band or something you can attach in front of you).
Yoga has been mentioned below, but I would add Pilates to the list as well, there are plenty of core exercises to go at.