Flybye - I wouldn't recommend doing something like this unless you're working with a coach. For many of the reasons that you mentioned, cumulative fatigue, risk of injury etc.
Now you could certainly make a tough goal and stick with it. Just not something so extreme. For running, consistency is key, so maybe you decide that you will run a minimum of 3 times a week and do one light run/form workout for 4 weeks in a row.
Living life like there's no tomorrow.
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