There’s no perfect way to train for any race; the best method is the one that works for you and your lifestyle. Whatever your reasons for wanting to train for a half marathon with three runs per week – whether it’s time commitments, past injury that makes you cautious about running more or you have other sports you enjoy – you’ll still be running a lot of miles over the 10-week plan, and it will still be challenge enough.
One of the big benefits of running three days per week is that you get more recovery days between those runs, so you may find you’re able to do a little more in each session than you would if you were training over four or five runs.