Runners knee - any advice gratefully received

[3boysNeedABiggerKitchen]

I have been doing HIIT, kettles and parkrun & off road running up to 6km for a year or so. I have a history of dodgy knees/hips/back, but have worked hard on my core, lunges squats etc.
I recently upped my mileage (mainly off road) toward 12km for an upcoming race and am now unable to run with knee pain in the front below my knee cap.
When walking I am fine unless I am going down a steep-ish hill on rocky ground.
I have 5 weeks until my race, I don't care about timings, I just want to jog/run it and complete it in one piece
I'm going to go for gait analysis at a local running shop and see if my trail shoes need replacing. I have taped my knee (thank you You Tube).
Is there any other advice out there?
I am gutted and frustrated!
Thanks in advance

Sounds like you're doing everything right. The only other thing would be physio I guess. Good luck, I hope you get it sorted.

Get a physio appt

I had chronic issues with my knee and calf - it's all because my gluteal are inactivated and my hip flexors are tight - it's thrown my whole leg out of whack and I'm doing specific exercises to strengthen my glutes

My physio says it mostly affects people who sit for long stretches eg at a desk and they've seen a massively increase in hip/gluteal issues over the last 5-10 years as more people spend longer at their desks

Thanks both. I do sit on trains and in the car, but I try (with the help of my Apple Watch) to move every hour.
I will try to do more gentle stretching too.
Off to find a physio!