Keep in mind that players need fitness to play soccer, but what type?
Soccer is a game of sharp cuts, sprints of 5,10,15,20-40 yds, jumping, side shuffles, turning, leaping and so on. It is not a game of long distance runs. Many players and coaches are under the belief a good 1 or 2 mile run will get them in shape. The issue here is that the soccer field is 100-125 yds long. Plus players must make short dynamic runs over and over.
As coaches you will serve your players better if you do not send them on long jogs. Shorten them up. Work 5,10,18,30,&40 yd runs with your team. Also include a ball(say a pass or head ball) at the beginning or end. Also always do fitness at the beginning of the training session after your dynamic warmup. NEVER THE END. It is better to work on fitness when players are fresh to get the most out of them. It is also best to give them rest to work ratios of 2 or 3/1. That is, if it takes them 10 seconds to run 18 yards, let them rest 20 seconds before the next one. this allows the players to increase their rate of recovery yet still go 100% each run.