After adequate warm-up, 8x 500's with 300m jog recovery interval.
I caught the 400m split and the final 100m split just to see if I was maintaining my speed. Here are the results: 82/20, 79/19, 79/19, 78/19, 77/19, 76/19, 76/19, 71/18
total mileage with 2 mile recovery jog, 7 miles