Pretty much only when working out hard and running as today. Was doing seated shoulder dumbell press with 32kg dumbells and it hit my lower back like a lightning 10/10 but managed to finish workout and got good in a couple of days. Basically I think that comes from my neck somehow. Need MRI to know more. But I wake up with neck pain sometimes and very rarely with lower back pain as my bed matress is medium and doesnt work for me, will change. Tried too many pillows n shit- no bueno as well. It's a tough one for sureDo you experience lower back pain only upon walking/exercise or sometimes you wake up with it without any exercise yet?