A few years ago just before Covid, I had sciatica. This is a compression of the sciatic nerve as it passes out of the spinal column between L4 and L5 of the lumbar region. The pain of this is very debilitating all down my right leg.
There are two fixes for this. one involving a surgical procedure and the other, the simple exercise of walking or better still riding a bike. Walking for me was really too painful but riding my bike around the village for 6kM early every morning did the trick. It's not a quick fix by any means but it's free and healthy. The fix took about 6 months and many other bits of me started working much better.
My doctor suggested I should use an exercise bike but quite honestly I find such things boring and less than adequate. Much more fun to ride around the village avoiding chickens, dogs, kids and angry old women.