My relationship with running has always run hot and cold, but this time I’m committing. My husband is the kind of runner who can do nothing for months and then decide to go out and run 5k without blinking an eye. I require a little more training. I registered for the Cambridge Half Marathon in November along with my husband, my brother, and a few other friends. So far I’ve been training for a little over a week and can run just under 6 kilometers in half an hour.