Some background: I’m a 25 y/o male, 168cm tall and weigh about 62kg (5’7” / 136lbs) with well-developed muscles for my size. I sit throughout a major part of my day and consider myself to be relatively stiff and inflexible - not a good combo, I know :(

I've been experiencing lower back pain/stiffness for about 2 months now that worsens with certain conditions/positions. Although the pain doesn’t hurt my ability to function generally, it’s become quite bothering for me since it’s always there to some extent (even when laying down). The pain is generally pretty dull, though it can get a bit sharp sometimes after staying in the same position (e.g. prolonged sitting). I can usually eliminate any sharp pain by moving around for a few minutes. Other than the last 2 months, I’ve never had lower back pain or discomfort.

The position that seems to aggravate my lower back the most is letting my back arch backwards while sitting, aka "slouching". It's especially felt after standing or walking for a long period of time, after which my lower back tends to become stiffer, making it uncomfortable to not keep a straight back. I can generally hit the "cat and cow" yoga poses without pain, though there is a slight discomfort when accentuating the cat pose.

I've had x-rays of my lower back taken and went to see an orthopedic doctor. His diagnosis: I have very minor scoliosis (which I’ve also had as a kid) which he found to be very negligible. He didn’t see any other issues with my spine and suggested that it’s “probably one of my muscles” and said I could go back to doing whatever I was doing. I used to do deadlifts but stopped ever since this happened. Strangely enough, on my last training session I was feeling the pain when lowering the weight, rather than pulling it up. I should mention that I’ve been avoiding such exercises completely since they seem to aggravate the condition.

Has anyone experienced something similar to what I’m describing? What steps should I take at this point to improve (or hopefully eliminate) whatever it is that I have? Responses will be highly appreciated.