Starting Position: Stand with your feet hip-width apart at the end of the ladder so it is directly in front of you.
Push off with your left leg exploding into triple extension (foot is plantar-flexed, knee and hip are extended) while picking up the right leg to step into the next square.
Push your left leg into triple extension (think about pushing the ground away from you) explosively drive the right knee straight up while maintaining a tall, straight spine; when the right knee is raised, the left arm should be forward in shoulder flexion and the right arm should be back in shoulder extension.
Plant the right foot in the next square forward, explosively drive the right foot into the ground to create triple extension with the right leg while explosively lifting the left knee up towards the chest; maintain a tall, straight spine while explosively driving the arms into shoulder flexion and extension to help maintain the forward momentum.
Bring the left foot down and place it in the next square forward and explode into triple extension with the left leg while driving the right knee straight up; continue running forward down the ladder placing one foot in each square and emphasizing explosive leg action to rapidly move into triple extension each time you are pushing off and moving forward; keep your chest lifted, your spine straight and tall and use explosive arm swings to help maintain forward momentum through the course of the ladder.
Exercise Variation: Instead of placing one foot in each square, increase the leg action to place two feet in each square; maintain rapid arm action swinging the arms forward from the shoulder joint.
Focus on explosive actions with your legs and pick the knees up rapidly--the faster you pick your knees up, the faster and more explosive you can move your leg into triple extension to drive your momentum forward.