I know exactly what you mean about losing focus. I can write 10 articles a day for Fiverr people but I can hardly write a few paragraphs of anything creative these days. How to ruin your chances of ever becoming a published author? - Join Fiverr!
However, I have a few tips that really might help. First, my recent fast saw me have my most profitable freelancing month out of over 3 years. In this case, maybe think about doing a 3-day juice fast or something to realign your focus?
Alternatively, (and perhaps much more practically) I was actually getting really depressed working all day at home sat facing the computer so I took a chance and bought a nice little Windows tablet with full MS Office on it + a keyboard. My idea was to test working on the move outside. So far, I can say that this is the best investment I have ever made. I now do all my article writing for Fiverr outside in cafes and bars etc, and only use my home laptop for video gigs.
Also, I have even been writing creatively again! I’m not trying to sell the benefits of a specific device. Rather, I’m just finding that working while people watching and being surrounded my all different kinds of goings on is a great way to boost my focus and get more done. That said I live in a very hot climate with a very seaside/holiday resort feel to it at the moment. In this case, I really am always outside, not actually inside a cafe or bar.
As for your running/ankle problem. If you can, I’d strongly recommend walking around barefoot for a while outside. I broke my ankle with a nice big snap a few years ago and they wanted to put pins in and everything as they said it would never heal properly. Thankfully, I had a friend who was very into natural health who told me to walk barefoot whenever I could, as this way all the little muscles in your feet and ankles which you don’t use usually are forced to start working out. In fact, the best place to do this is at a beach.
Anyway, I walked barefoot for months after that and was left with the kind of feet and ankles which some people fetish after.
In either case, good luck!