It's certainly a good place to start and anything is better than nothing. Take things easy to start with if you're really unfit and slowly build up speed. I walk to the railway station each morning to get to work and comfortably cover 2 miles in just under 30 minutes. Do that again in the evening, plus whatever you do just going about your normal business during the day, and it's surprising how far you actually cover.

The next step up (pardon the terrible pun here) is to use the stairs more. If you use a lift (elevator) at work, get out a floor early and walk up the rest until you eventually walk up all the way. Again build slowly and your level of fitness will rise. I'm 3 months into the paleo lifestyle and now run up and down over 120 stairs every working day (sometimes more than once).

Apart from that, the only exercise I get are a few (and I mean only a handful) of air-squats, sit-ups, push-ups and a plank. Oh, and running around after the family and running a Scout group.

Welcome!

I'm hardly one of the "experienced" folks - I'm only about 6 weeks in. But I'd just like to offer encouragement, and agree that it's actually pretty easy, which bodes well for maintenance. I find it's suiting me well and I don't have that much trouble not eating things I thought I would really miss.

Your mood swings may be related to crashing blood sugar; the good news is that this will probably get better as you get better at burning fats (and also as you vary the kinds of exertion you do). Watch out, though, in the meantime as in the first few weeks low blood sugar may pose an issue even without the exercise.

Walking is a great place to start with exercise.