Below are still shots of Jeff and I running and I am going to try to analyze run form..
In the first picture you get a sense of arm carriage- we both carry them up and relaxed. Dropping your hands down by your waist will only increase the amount of energy you will use. Arm drive only needs to be powerful when you are sprinting.
You can also get a sense of our foot plants. We are both about to land and you can see that neither of us are dorsi flexed for a heel strike. Jeff's ankle looks very relaxed and effortless. Our forward knee drive is just that- forward, not vertical. There's little need to lift your knee, rather think about letting your leg easily swing through the forward arc and 'fall' back down.
In this pic you can really get a sense as to how much we swing our arms. Both of my hands (and Jeff's) are next to each other. We swing from the upper arm and shoulder to counter act the leg movement. This requires a strong core.
Our 'kick back' is nice and strong showing good forward movement. If you look at me you can see that my right knee is not that far back- this illustrates how much I 'sit' in to my pelvis over my striking foot.
Below are two good pictures of our spine and shoulder alignment. Our spines are supporting our body weight efficiently with just enough forward lean to promote forward movement. Our shoulders are nice and parallel to the ground although Jeff does 'shrug' his shoulders. See the difference between us? There's no need to shrug the shoulders, but it isn't necessarily incorrect. It's hard to fault a 2:40 marathoner and 3:00 Ironman runner! Oh yeah- he also ran a sub 1:50 800 meters in college!
And while I'm nit picking (sorry Jeff), his right hand is 'flopping' downward. I see this a lot in runners and this hand movement can be linked to leg fatigue. Simply relax your hands and pronate them upwards slightly so your palms are facing up. There's little need for wrist movement or tension in your hands.
And now my favorite picture. This is what fatigue looks like (Jeff trains for Ironman and is putting in an amazing amount of training on top of a full time stressful job!). You can see that his head drops and his spine is out of alignment. This increases energy expenditure at a point when efficiency is critical. Fatigue at this point would increase exponentially due to a loss of economy. His lower back is arched, head is down, arms are tight, his right wrist is suppinated even more than before.. Lots going on here! This is all due to fatigue but can be corrected with conscious thought. To me this shows that Jeff's 3:00 run at Kona last year was well outside his potential.