Keeping perfect form while running is difficult. For me, especially when I am getting tired, my form starts to fall apart which makes everything harder and my movement less energy-efficient. Here are some cues you can remember to keep your form strong. Taken from Doug Stutz book "RACE YOUR BEST":
Focus on technique cues throughout the race to improve your running economy-- in other words, run your fastest while using your energy most efficiently.
Technique Cues
Run Tall: Imagine you are a horse on a merry-go-round. You are anchored in position by a pole, which keeps your head, torso, and hips all in line, centered over each other. The pole keeps your head focused straight ahead--it can't move up and down or side to side. The pole keeps your head centered squarely over your torso. The pole keeps your torso centered squarely over your hips. So as you run, Run Tall like a merry-go-round horse with a pole keeping your head, torso, and hips all in line and centered over each other. Run Tall!
Brook Trout: Before beginning this cue, make the scariest face you can and hold it for 5 seconds. Relax your face for a few seconds, and then repeat making a scary face. Relax again. As you repeat this one final time, focus on what happens to your jaw, face, and neck as you relax. What happens? Your jaw drops, your mouth hangs loosely open. Because the jaw relaxes, the rest of your face and neck muscles also relax. When you picture a Brook Trout, see its big jaw just hanging there... So as you run--whether you're running fast, moderate, or slow--remember the Book Trouth with its jaw dropped and mouth hung loosely open. Brook Trout!
Shoulders Down: Before performing this cue, make your shoulders as tight as possible, and hold them there for five seconds. Relax your shoulders for a few seconds before tightening them a second time. Relax again. As you repeat this one final time, focus on what happends to your shoulders as they relax. They should relax and drop down. (Depending on how you held them, they also went forward, back or just straight down.) As you run, ask yourself, "Are my Shoulders Down?" Shoulders Down!
Light Hands: Before addressing this cus, make as tight a fist as you can with each of your hands for five seconds. Relax your hands and drop them to your sides, [repeat]... Then, while keeping your hands at your sides, and without moving your fingers or wrists, ask yourself "What do my fingers and hands look like right now, when they are in a relaxed position?" You will notice your fingers are in a slightly curved position and that the tip of your thumb and the tip of your index finger are almost touching. You will also notice there is space between your thumb and your palm, allowing
light to pass through. This is how your fingers and hands should look as you run!
... Tight hands lead to tightness throughout the upper body, which is counterproductive.
As you run, remember to keep your hands and fingers in a natural, relaxed position. Light Hands!
Thumbs Up: ...This does not mean that you literally want to have your thumbs sticking up as you run... you don't. But if you did, would your thumbs be pointing up or pointing in? If you drew straight lines from each of your thumbs to the heavens, would those two lines be parallel or would they intersect? As you run, ask yourself "Are my hands positioned to keep my elbows close to my torso? If my thumbs were sticking up, would they be pointing straight up or in a little?" Thumbs up!
Chest High/Hip Pocket: What should your arms' range of motion be as a distance runner? As your arm swings forward, your hand should raise to somewhere between your navel and chest. As your arm swings backward, it should reach your hip pocket. As you race, the range of motion for your arms should be from Chest High in the front to Hip Pocket in the back. Chest High/Hip Pocket! Note: When running faster than this pace (ie. sprinting), the range of motion increases in both the forward and backward arm swings. The key is to keep the motion as smooth as possible...
Arms Forward, Straight Ahead: As your arms swing forward, they'll naturally come across the torso somewhat to counteract hip rotation. However, your arms should not come so far across the torse that they contribute additional unwanted rotation. In the forward arm swing, no part of the hand should cross or even touch the mid-line of the torso. You should direct your arms forward and straight ahead. Arms Forward, Straight Ahead!
No Robots: Although Arms Forward, Straight Ahead is an important cue, remember that your arms need to come across the torso somewhat to counteract hip rotation. If they were to literally swing straight back and forth like a robot, they would not generate the counter-rotation necessary to keep the body moving forward efficiently. No Robots!
All Five Toes: As you push off the ground with your foot, focus on pointing the foot forward rather than in our out. If you naturally underpronate by coming off only the little toes on the outside of your foot, or if you naturally overpronate by coming off only the big toe, recruit the muscles in your other toes to add more power to your push-off. All Five Toes!
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After you have done a few sessions practicing these cues you will begin to feel more comfortable with the technical improvements your are seeking. Then you will be equipped to cycle through the cues one-by-one, doing a self-check to see if you are performing each cue correctly and energy-efficiently...