Back in high school, I hated running - I was neither in a good shape, nor did I have the technique to compensate for that. Accordingly, I usually gassed after half a kilometer.
I was rather astonished when, during my stay in Tel Aviv in fall 2000, I felt like running a few kilometers (the beach there is perfect for jogging) and I did not drop dead afterwards. The year after, I chose to try this again and sign up for the amateur course of the Residenzlauf, an annual running event in Würzburg. After I had I survived that as well, jogging once or twice a week became habit.
Of course jogging is one of the best ways of increasing cardio endurance (which is needed so badly in judo). However, that would hardly have motivated me to do it regularly if it didn't have other advantages as well: you do sports outdoors, which is incredibly uplifting if the weather is fine and the course is beautiful (such as the vineyards around Würzburg). If the pace is not too fast, you can even talk with other nice people (greetings to Monika, Claudia, Christan and Annette). If you are alone, you can go with the flow of the motion and think about all sorts of things. And you experience the built-in painkiller hormones when, after half an hour or so, all fatigue disappears and you fell that you could go on forever.
If you want to try it yourself, you should pick a course with nice landscape or a park, and start slowly. Initially, the crucial point is not to go anaerobic - otherwise it's "game over" very quickly, with stitches in the side, short breath and heavy legs. If you get enough oxygen, you can carry on for a surprisingly long time. Also, get a pair of decent running shoes (for the sake of your joints) and look out for people with a similar training state to jog with. Have fun!