Today I had a meeting that spanned my entire working day in one room, including lunch. For someone who usually must get outside for a lunchtime stroll, even just around the block, it is quite a feat.
To make sure you fit some outside time into your day, try walking from the station instead of taking a cab or coach. In my case, I caught a slightly earlier train and walked along the river to the meeting spot. And the return walk to the station was just as lovely. Who knew Bedford is good for a stroll.