6min/miles is friggin good for 5 miles. And the test helped you get to that competitive level? Were you doing hills and repeats in your routine to get benefits from the aas?
My running was always done on the treadmill because it was more convenient and I could precisely control the incline and speed. On Monday I would do hill repeats, in which I would set the incline at 9% and and sprint for 3 min, followed by a 3 min rest. It came out to 5 total repeats in 30 min.
I always tried to run at a speed higher then the last repeat that I had just completed.. I found a good website,hillrunner.cXX/training/tmillchart.php that shows the pace conversions.
This is important because people obviously run slower going up hill then flat, however V02 consumption could be equivalent to running at a faster pace, which will help you when you're running on a flat surface. I found it was a constant battle between building up your v02, to training your fast twitch muscle fibers to keep up with your lungs..
That was the only dedicated day I put toward running. Every other day, I ran at an 2.5% incline for a straight 30 min, pushing as hard as I could. I did this before lifting.
Here are some things to keep in mind. I found test to be hard on the joints, so cycling with EQ, or deca will help. Tauring will prevent calf pumps. Beta-alane and cordyceps work wonders in increasing V02.
Cycling off I did lose speed / endurance. I only achieved the 6min/mile at the end of my cycle. Now I run at about 7:30 min/mile, but I'm slowly going back down in time. I believe the muscle memory is still their in the legs.
Oh and the great thing about the cycle is that you burn off fat and still maintain a good amount of muscle. While I didn't really increase in size, I did increase in strength. I'm more into that toned look now. Let me know if you have anymore questions, I'm currently training for OCS.