Designed for beginning runners or anyone who is planning to run the half marathon distance for the first time, this training plan is based on five days of running per week, with the once-a-week long run set on Sundays.

> 12-week training plan

Spread out over four months instead of three, this training plan is designed for runners who've run a half marathon already and are in need of a training plan that can fit into a busy schedule -- with four training days each week vs. five.

> 16-week training plan

For runners who are looking for an even more gradual buildup to the half marathon than the 16-week plan offers, this five-month training plan starts slowly and builds toward the 13.1-mile race day, with both four- and five-day-a-week runs later in the plan.

> 20-week training plan