I am currently visiting Madrid after spending 2 years in Tokyo, so I am taking some pics from those places I pass by :)
I used to live near Canal de Isabel II Park in Madrid. I remember coming here everyday for doing some sports (mostly walking or running). While this park is not widely known, I feel it is one of the bests in Madrid.
The park has open areas for running and walking. It also has some sport courts that can be booked.