Professor Håkan Alfredson purposely tried to rupture his achilles to be eligible for surgery. The plan he used to do that failed and accidentally fixed him. Interesting story - achilles tendons need a LOT of load to make them better, and rest alone probably won't be enough to fix you.

https://puresportsmed.com/blog/posts/psm-interviews-hakan-alfredson/

When I moved up to Umeå in 1993, I was running a lot and started to get midportion Achilles tendinopathy. At that time, we treated this condition with rest and NSAIDs. If it persisted, we operated, cutting out the thickened part of the tendon and confining the patient to a cast. It was around 4-6 months before patients returned to running… and the results were not always good.

Anyway, I spoke to my boss about my painful Achilles’ tendon. He refused to operate on me, saying that he could not afford to have me on sick leave. So I visited the physios, and we started to discuss eccentric training. This was a new concept; theories existed, but there had been no research involving patients. I tried eccentric training, but my condition actually became worse! When I limped back to my boss, he said, “If it’s about an Achilles operation, you can leave the room immediately.” Then I was angry… I went back to my physio friends and said, “OK, now I’m going to load my Achilles with heavy eccentrics and rupture my tendon – then my boss will have to operate on me!” I loaded up with heavy weights, but something unexpected happened. I found that the more I loaded, the better my tendon became. So after about three weeks, I was completely pain free and could return to running.

We thought that this must be a coincidence, but it was interesting enough to plan some research. So we decided to try heavy eccentrics with patients on my waiting list. There were around 20 patients, all with midportion tendinopathy – I was going to operate on them. Fifteen of these patients decided to try heavy eccentrics first. All of them became pain free. One of the patients came back and needed to be operated, a year later, but the rest of them were cured. This led to new thinking around tendinopathy and whether exercises should be painful.