According to the tales of “old housewives” and the assurances of hippies, food does have a supportive role in helping tendon pain resolve itself.
There are famous anti-inflammatory foods that, when combined with a healthier lifestyle and actually doing specific exercises, really, really helps.
The claim by some fitness experts that physical training can deal with endometriosis was fascinating news to me. I keep an interested (not obsessive) eye on the literature and I clearly recalled the last proper review was by Camila M Bonocher et al in
Endometriosis and physical exercises: a systematic review.