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I suffered a knee injury back in July, that I had a friend of mine (he's a physiotherapist) look at briefly. His diagnosis was that I suffered either a minor MCL tear, or possibly a minor meniscus tear.
I have been working on it and it's almost back to normal, despite causing me some trouble in case of strong impacts on the fully extended leg, or with excessive strengths applied to the outer side of the knee. (In those cases after a 30 sec / 1 min rest I'm 100% back).
While so far I have been doing any type of workout I know involving legs in general in addition to tyring to lose some weight (being a little over 90kg doesn't help), I would like to focus more on strengthening especially muscles, ligaments, and tendons around the knee, to prevent future injuries as well as avoiding excessive stress on the injured area.
What type of workout should I focus on? Body-weight exercises and running preferred over gym, cycling, swimming, etc., due do logistic reasons.