I asked a question about a similar problem on Elite a while ago. The following is my original question and the response by Michael Hope....
Today I did Good Mornings for the first time in a while and I had a sharp pain near the bottom of my glute or top of my hamstring on the left side. I don't feel anything on the negative or the pause at the bottom but as soon as I begin to lift the weight there is a sharp pain that feels like it is pretty deep. I could feel it even when I was warming up with the bar so I don't think it started today. I tried some light romanian deadlifts and those hurt on the concentric phase too, and I do heavy RDLs alot and I've never felt this. I tried doing full squats and those have no pain at all. I am just coming off a rest week and before that I hadn't done and GMs or RDLs or DLs for over 6 weeks at least. I had been doing mostly full squats although I remember trying some lunges a few week ago and this area felt a little pain with my left leg forward so I might have had this injury for a while and not noticed it. Any ideas what it could be and what I should do?
Josh let me tell you a story and see if this resembles your problem
I am treating a 17 year old football player that has a 7 week history of hamstring strain at the origin. He has pain at the bottom of his butt top of his hamstring like you. His pain is intermittent. He has pain with running, RDL, GM and DL. he stopped the following exercises because of pain. he stopped all lowerbidy training.
On testing he had no pain with resisted hamstring testing. He had pain with prone hip extension, bent knee hip extension and bridging. He had pain with anterior reaches, RDL and GM with no weight. He had no pain with squatting.
I had him perform 30 bridges, 30 prone hip extensions 30 bent knee extensions and 20 GM.
Every rep of every exercise produced pain, but the pain never remained worse. This meant that he has a stable painful problem. He is an inactive lesion. He needed to contract the muscle and stretch it for recovery. preferable with the same movements that created his pain.
His treatment was to repeat the previous exercises 3-4x a week as well as squatting and lunging. He would perform 10 GM with just his body weight 5x a day. The goal was to produce his pain with the GM. The GM was a two fold exercise stretch the problem and contract the tissue
Once bridging and prone hip extension exercise were no longer painful second week. He began stability ball bridging. he added db's for GM. He would pyramid up in weight just to see the pain respone. It was consistent... the exercise produced pain but when the exercise was over his pain stopped(not worse). Still a stable problem. Which means we are not making his condition worse. The plan was to give him enough exercise stimlus to repair the structure but not enough to push him into an active painful condition. He gets worse and remains worse with his exercises.
On his second week I let him run sprints. One day his response was... pain was produced but did not remain worse. Next day was faster shorter sprints this did make him worse for only twenty four hours. No big deal
In his third week he had very little pain with resisted hip extension. The most pain was the GM movement. heavy dumbbells or his body weight gave the same intensity of pain response. At the end of this week he will have been seen for three weeks. He is sprinting with very little pain and does not remain worse. He will play this week
You may find your respone to movements like my young athlete. If this is the case try some of the same exercises. If these baby exercises hurt the big ones will definetly cause pain and inmost cases to much tissue tension.
Rememebr your are not trying to improve your strength just give the muscle the proper stimulues to heal. Squatting can be continued
Sorry for such a long response let me know if this makes sense
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