So last Thursday was doing back and using the hammer strength back machine and I do 1 arm pull down at a time. Well had 4 plates got to the 3rd rep and felt a shock in the middle of the bicep, well I thought I tore it.I took 3 days off and did some shoulders and some heavy triceps and so far so good. No bruising no bumps or lumps or indentations so I must of just pulled it. I did purchase some of the BPC 157 so when that comes in I will use it to help the recovery. Right now ts sore a little but wont be doing any Bi's or back workout until I know its ready. Its still a little tender