I had tendinopathy in my foot for literally years, it had progressed from tendonitis. I saw 3 different doctors, had custom orthotics made, spent $500 out of pocket on physical therapy, had Graston done, had an MRI (it showed the tendon was thickened and scarred), and one doctor wanted me to do pricey cold laser treatments (no thanks!) I randomly started taking Great Lakes collagen powder because I know some other runners who take it for recovery -- well within a month of taking it every day my tendon pain that I had suffered with for 2 YEARS was gone. GONE. I have been taking this collagen powder daily for 5 years now and I will take it for the rest of my life if need be. (I tried other brands and they did not work as well, my pain came back after a month.) FYI you lose collagen as you age, and tendons are made of collagen. You can go on PubMed and do a search for scientific studies about how collagen helps tendons. Also, I have Lyme disease and Bartonella (I was misdiagnosed with "Multiple sclerosis" by 4 neurologists, I have lesions on my brain from Lyme) -- and what I did not know is that the Lyme bacteria (Borrelia burgdorferi) eat the collagen in your body -- which causes tendonitis. Stephen Buhner's book "Healing Lyme" actually recommends this same brand of collagen if you have Lyme. I hope this information helps someone out there who has been suffering with tendonitis for years. BTW I asked my doctor "Is there anything I can take, nutrionally?" and she said "maybe turmeric?" Doctors are clueless about nutrition. Doctors are clueless about Lyme, it's an epidemic, and it is everywhere now. If you have been told you have "MS" or "chronic fatigue" you need to see a LLMD and get a Western Blot test done through Igenex or Armin Labs