"Hey Coach, What About Me?"

To slightly paraphrase something I once read, "Your body is not like everybody else's body". That's a question ever runner should ask whenever they hear the workout for the day. Here are four things to focus on each day as you run through the woods.
Arm Carriage
Some athletes tend to carry their arms too wide (110 degrees or higher) and others too narrow (75 degrees or smaller) and tuck their elbows in like a marsupial. The ideal for those running distance is somewhere in the middle. Arms usually act as a counterbalance when running easily. As tempo increases, so should the action of your arms. Think about keeping your arms at about hip level with the hands crossing about the waist in the follow through. In addition, arms should never cross the body's centerline.
Toe-off (Power)
One of the most common seen flaws in runners is the lack of "toe-off". This usually is a result of weak Achilles or calf muscles or too stiff running shoes. Good old fashioned stadiums (yes, the ones you did as punishment in P.E.) can achieve great results. Shoes with greater flexibility allow a runner's feet to function more naturally with far greater power in the "toe-off".
Knee-lift & Rear Leg Extension
Greater knee-lift should not be emphasized in performance based distance running, but the amount of drive fired through the hamstrings and into the Gluteus-all fired to the rear, not the front. The "butt-kick-drill" is an excellent training for this. And should I say, yes-HILLS!
Sitting In The Bucket
Note-the gluteus, hamstrings, calves, and even the lower back muscles are both invaluable and interconnected as they relate to forward movement. All of these muscles are forced to work HARDER when an athlete runs while "sitting in the bucket". In other words, when your arms are below your - _ _ _ _! Moreover, tightness in the shoulders can force a runner to hunch and will exacerbate the 'booty'. Keep your oblique strong and be sure to stretch your lower back regularly. Make sure your hamstring muscles are strong and flexible.

All runners have different forms. And yes, running "properly" is indeed a subjective assessment. BUT, there are a number of form maladies that can inhibit you from moving forward powerfully and efficiently. Next time you go for a run think, "What About ME?"