I moved to San Francisco in 2001, and lived there for about a year and a half. I worked at a lovely architecture firm in North Beach, and lived in Nob Hill. I used to walk to work every day. About a mile and a half each way, up and down two big hills. And I loved it. Every minute of it. I would usually walk through chinatown (which was always an adventure.) You see a lot of things early in the morning that you would never see once the streets are crowded with people. Anyway, back to my point... there are so many positives about walking to work. It relieves stress, allows you time to think, gives you some fresh air & sunshine (or fog if you live in SF), it's just so beneficial to your health. The best shape I was ever in was when I lived in SF, despite the fact that we went out to dinner at least three nights a week. Now that I live in LA things are a little different. I still "walk to work" most days, though I now work mainly from home. 

So here's my suggestion, even if you work from home try "walking to work" in the morning for a few weeks. It doesn't have to be long, just a half hour. Try to include some hills. See how you feel. Are you more productive? I'm willing to bet you will be. If you like, add in a "walk home from work." Then come back to this post and tell me what you think of this new healthy habit. It's one of my own personal favorites, and I am thrilled to say that I created a healthy habit in SF that, with a little modification, I still enjoy in LA. 

ps for all my LA friends who are reading this, I realize it probably confirms what you had suspected about me all along. I am a nerd. Who likes to take long walks.