For the last 6 years or so I've been plagued by a persistent lower back pain. It manifests during running around the 1km mark every time. A warm sensation in my lower back that gradually gets worse until it turns into an unbearable cramp.

I attended physio for months but they were convinced it was due to weak hip flexors and prescribed me exercises that didn't have any effect, the pain subsided long enough for me to stop going (I put it down to a new pair of trainers, but don't know what actually helped). But it didn't take long for it to return.

For the last few years I've been dealing with it by having different "seasons" in the winter I'll powerlift and not jog at all. When summer comes around I'll take up running again, the first few weeks are always painful but eventually it fades.

It's a pain in the arse. Pun intended.

After discussing the matter with colleagues who have had the same issue it seems my physio may have missed something blatantly obvious.
Now to say I'm not a flexible person is an understatement. While some people can keep their legs straight and touch their toes, and some even rest their palms flat on the floor. I wince trying to reach past my knees.

When hamstrings are that tight it makes sense to me that a running gait could almost be a stretch every stride, a bit like lunges. If that's the case my back could be getting pulled at, or moving into a bad position to try and stop the stretch.
It also makes sense that powerlifting would be making it worse, not just by working the back muscles with exercises like deadlift, but the muscles tightening during repair.

To test the theory I had a long stretching session before a run and managed to hit 2.5km with a much lower amount of pain. Not fixed, but an improvement.

So it hurts to admit it but squats and deads are going to have to take a back seat while I fix myself. I'll try and maintain my strength levels but 5x5 stronglifts is going to be paused. That's right I'm skipping leg day.