Trying to get back into shape is a very difficult task if you've been away from it for a while. The last time I ran 10k was now half a decade ago.
Since then, I've been fairly active but that is a farcry from being able to run a full 10k let alone quickly.
I begin my lifestyle change diving in the deep end. I run a forced 10k everyday no matter how I feel and no matter how slow or how fast.
The weather isn't good for running out doors and with my heavier stature, it should be easier on the knees.