Just wondering why my lower back feels like a heart beat a lot of the time. I just mad an MRI and it came back all as normal. My back has been sore for about 12 months now. Only in the lower part nowhere else. It seems inflamed. I do a lot of physical activity, boxing, Brazilian jujitsu, gym, swimming. The Dr has just put me on anti inflammatory tablets. I have stopped all my activity for a week now and just continued swimming. My back is not quite as bad but still odors, no matter if I sit, lie, walk. I Amman working so I am not completely resting it. What is the heartbeat sensation and it feels like it is squeezing or twisting sometiimes