Having been a runner since the mid 80's, I want to share with you what I have learned over the years about running form and efficiency. When your form isn't good, you end up wasting a lot of energy and sacrificing precious seconds or even minutes from your time.
1. Run with your shoulders down and back. Think about pulling your shoulders away from your ears. This releases tension in the upper back and forces you to relax more. Hunching forward isn't good for posture either.
2. Don't let your arms cross your midline. Instead, keep your elbows at 90 degrees and focus on forward and backward movement of the arms. You waste a lot of energy when your arms are crossing over your torso and back-and this is not the direction you want to be moving in. Imagine your arms pulling you forward and mimic that movement.
3. Strike with your mid foot or fore foot. This is much more efficient and better for your joints than striking on your heel. Many runners prefer heel strike or have just run this way for a long time and don't want to re-vamp their form. If that works for you then stick with it, but in the long run you'll want to work on striking the ground under your hips with your mid foot or even fore foot. This is kind of strike provides much better shock absorption to your ankles, knees, and hips. There are a ton of drills out there to teach yourself to learn to run this way. Check out my YouTube video here for some great running drills to help you with your form:
4. Don't clench your hands too tightly. Using muscles to hold a tight fist is a waste of good energy. Instead, let your arms fall at 90 degrees, let your wrists relax with a relaxed bend in your fingers. Wasted energy will cost you seconds or even minutes.
5. Lean forward. Stay ahead of your foot strike just a little bit with a forward lean. This is much more efficient than being upright for the duration of your run. This forces that back leg to swing up and around then strike quickly and more efficiently.
6. Avoid shallow diaphragm breathing. Try to breathe by sucking air straight down into your belly and let your abdomen fill up with air first. Shallow diaphragm breathing forces you to take more breaths to get enough air. Breathing deeper relaxes you too and helps you get into a steady rhythm.