Lower Back Burning Out Very Quick

yesterday i was doing some complexes and by the time i got to the last two sets my lower back was extremely stiff. i could barely walk afterwards. i layed out on the floor for about 5 minutes and i was ok afterwards.

the same exact thing happens when i run and do jump rope, my lower back gets really really stiff and it hurts a bit. why is that?

Dude I had the same problems earlier this year… long story it was just a cumulative build of weightligting, muay thai and jiu jitsu. Way to much volume with hardly resting… But the point is, is that I didnt get it checked out for a while and I ended up having a DISC protrusion.

Was painful, couldnt jump up and down, lie on a bed, sit at all or anything…

So go to a sports physician at a sports institute and get an examination of your back. Either you will get a whole bunch of physio-therapist exercises to do and drop deadlifting and squatting for a while. Work on your core strength. Drop any abdominal exercise that causes flexion in your spine ( ie crunches). But the sports physician might have you do an MRI scan to be safe, thank god I did cuz there can be many things wrong with the lower back.