Functional Warm-ups
One of the major draws to the boys' and girls' volleyball programs at my old high school was the fact that the coaches rarely made the players run. In fact, it was one of the defining characteristics of the program which drew me into the sport to begin with. It wasn't a matter of being lazy, more a fact that running was boring, repetitive, and had no immediate "fun" factor to it.
But this wasn't the reason why we rarely ran before or during practices. No, the reasoning was much more logical, and wouldn't be revealed to me until I began to coach under them a few years later.
The fact of the matter is, especially at the high school/juniors level of competition, that running provides very little benefit. You can even consider it a complete waste of time. If I haven't already blown your mind or completely offended you, please hear me out...