One of the many things that sets the Boston Marathon apart from other marathons I’ve done is that the training has to be completed during the cold, dark winter months. From November through mid-April, I’ve been getting up early, usually in the dark, to run in all kinds of uncomfortable weather: bitter cold, snow, freezing rain, howling headwinds, you name it. And this having been a particularly rough winter, I’ve frequently had to train in a combination of these conditions.