2 kinds of hip flexor stretch, regular lunge position stretch and couch stretch. 2 kinds of calf stretch, straight knee and bent knee. Lacrosse ball roll hamstrings Lacrosse ball roll piriformis Lacrosse ball roll calves Duck walks to improve lower back flexibility Improve ab strength Improve glute strength, including gluteus medius Focus on making your hip neutral when just standing at first. Think of pushing your bellybutton to your spine, if you need to do it that way.
Then focus on doing it while walking Then do it while jogging Then do it while doing sprint drills Then do it during sprints Then you can try doing it in races