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McFadden's main problem is he runs too high going through the line of scrimmage as seen in the photo.
Perhaps he did too much track work with Michael Johnson and forgot about his football fundamentals. To run at your max velocity, you must run up tall and open up your stride.
Running football, the only time you want to be up high is when you've gotten past the defense.
It could also be a problem brought on by his coming out of school early. It usually takes a while for a collegiate coach to correct these flaws in the athlete.
The problem with McFadden was the coaches had to play him as is with the speed he has.
The problem of running too high is three-fold.
Making people miss is impossible because you need leverage to change direction fast. Changing direction at full speed requires you to sink your hips and you have to slow down to sink them if you run high.
Now the defender has plenty of time to react.
You will also have problems pushing the pile and breaking tackles if you run too high. Running low requires you to have bent knees and bent knees are need to absorb a violent collision.
Straight legs can't absorb violent collisions so the shock causes those straight legs to go dead or collapse. This is what causes McFadden to go straight down on the first contact.
Then there are the injuries.
Running low helps with upper-body contact because your bent knees can absorb it without hyper-extension or twisting. It also keeps your pads down to stop your legs from getting hit to cause injuries.