http://running.competitor.com/2014/03/training/early-season-strength-building-hill-workouts_96706 http://japodrunner.blogspot.com/2014/03/western-states-100-old-school-race-with.html https://www.youtube.com/watch?v=7hdL65J8m9A https://www.youtube.com/watch?v=54DtVXjk2jY http://well.blogs.nytimes.com/2014/03/07/why-high-impact-exercise-is-good-for-your-bones/?_php=true&_type=blogs&_php=true&_type=blogs&_php=true&_type=blogs&_r=2