After a 3 mile warmup I ran 5 miles of fartlec. 6x1/4 fast with 1/4 recovery. Then 3x1/2 with 1/4 recovery. I wanted to run about 6:00 minute pace on the faster intervals and couldn't believe it felt that hard. By the time I got to the 1/2s I couldn't even keep the pace at 6:00 and ran them a lot slower. I think I may have had some fatigue from Tuesday.