Discussion: Sore back

I'm assuming it's lower back pain, so could be linked to the core you've been doing? Some exercises (like sit-ups) can place a bit much strain on the lower spine

Alternatively, if your core is significantly stronger than your lower back, that can also cause pain... Though also if it's significantly weaker that can cause pain too, but I figure it's pretty strong by now!

Anyways, I don't know what core you've been doing, but if there's not been much lower back work in it, maybe worth chucking in a few exercises like Bird-Dogs and seeing if it helps some?
Not that I really know anything much, but I figure it's worth a shot ¯\_(ツ)_/¯

I'm doing a selection of youtube videos, but its not just core- there's some arm ones/leg ones (for injured people lol) and these videos are pretty good at mixing the workout up!... I have come to the thought that I went a bit too far on the roll-outs on Sunday/generally too much, but it has improved significantly with rolling :)
Cheers though expert Andrew!