Thank you for the article. I find brisk walking (at the speed of approx. 5 km per hour) extremely helpful for this, plus it doesn't require preparation time like in case of jogging or swimming.
I find interval training very helpful i.e walking 60 secs @ normal pace while jogg for 30 secs.(you can amend the durations according to suite you as i have just started)
i do 8-10 sets and they are great for physical and mental fitness.