This Half-Marathon training plan (up to 20 weeks long) includes my tried and true, scientifically-based and proven half marathon workout sequence. You'll improve your endurance with progressing long runs. You'll boost your stamina and speed with my marathon specialty workouts and I'll have you perform several goal pace workouts so you really dial in goal pace. And speaking of goal pace, this plan includes several of the predictor workouts I use with athletes so you can be absolutely sure of ...