Eh I disagree. Until I have side by side year to year comparisons I can't really say they have become bigger faster or stronger. Just my opinion. Gbr93 google linear progression and how to add serious muscle and get back to be. It will not include running more. Hate to hurt your feelings.
That's just it. If you would have looked and paid attention to what the players have even said. A metabolic circuit includes zero running. What it does is put every lift on a certain time schedule. For example, you have a certain amount of time, say 80 minutes to complete all of your reps and sets. Squat, bench, deadlift, rows, curls, pull downs, what ever lifts you want to incorporate are all on a schedule. You finish your set in 20 seconds instead of 30, then you get a little longer to rest before your next set. However, you take a minute then you have to go straight into your next set. It forces your body to perform under extreme conditions. That's why they were saying they were so tired, not because they were running, but because their lifts, sets, and reps, we're so fast-paced you can't catch your breath.