Watch any soccer game and you will see players who can cover distances very fast and others who seem to be able to navigate congestion in the penalty area with ease. The player who is accomplished at both is rare.
Numerous research reports show that agility and speed are different characteristics.
As with speed, agility has many components, including:
Recognition/Reaction: Recognize the situation and react ASAP
Decision-Making Speed: Moving as fast as possible while assessing game situations
Balance/Body Awareness: Controlling and knowing where all body parts are all the time
Footwork: Full control of the feet
Change of Direction: Rapid and accurate changes of direction
Obstacle Avoidance: React quickly to obstructions in running path
Improving agility improves quickness both on and off the ball, body control and prevents injury.
More on Soccer Speed Training
Footwork is critical to agility. The common error is a short back step before moving in the desired direction, which lengthens the total reaction time. The more proper "first steps" are the cross-over step (used for great distances, the back foot crosses over the front foot while the main push is from that front foot); open step (the lead foot steps out not too far and the push comes from the back foot); jab step (the lead foot steps slightly back and turns in desired direction--the push comes from the back foot); and the drop step (the lead foot drops straight or diagonally back while the push comes from the back foot).
I could never do the drop step--a European teammate in college said I had American feet. Picture this: You are facing the dribbler who manages to give a feint to your right and go around you to your left. My European friend would take the feint. Now his right foot is out where he took the feint and the left foot is back; basically the starting position of the drop set. Instead of running around this foot placement (like me), he would just swivel on his feet (no steps) as they were planted and end up with the ball at his feet. Try it. It works.
Quick recognition of the situation, drop step, turn, and there is the ball. My friend could do this so quickly that he would get called for obstruction (by the American refs who didnt understand the move) and then get very mad.
Our college team once played a seriously good English team. One of the many skills they demonstrated as they destroyed us was the ability to cut in one step. It took us three or four steps to try to keep up.