maybe a bit less HIIT and a bit more yoga in your life could help?!

that lower back pain thing is horrible... and you'll want to take care of that before it gets worse over time... the "3rd world squat", I dodn't know if there's a more politically correct term for it... but that's what helped me with compression related problems in the lower spine... do that for a few minutes every day, if you're able to even reach that position, to give the tendons a good stretch!