I was discussing this with my wife just a little earlier - central London is actually smaller than you might think. My phone map app in walking mode indicated Euston Station to the northern end of the Strand is only about 1.3 miles on foot. Basically you walk in a straight line down Kingsway. I did it in 20 minutes each way (the phone suggested half an hour

). I don't live in London, I was attending a business function and Euston Station is my usual route into London. I am now doing a lot more walking to meetings in the West End from Euston. I estimate that I am now walking over 20 miles a week more than I was before I was diagnosed and occasionally a lot more. One problem is that my shoes are now a tad loose because you lose fat off your feet as well.
Edit: I ought to add that last night's food wasn't low carb but I managed to avoid the bulk of the carby bits and had no pud. But I did have couple goes at the rather nice mashed potato and gravy...