Comfortable & consistent warm up. Disappointing tempo run. Target was 9 to 9:15/mile. First half mile at 4:35+ was right on target, but even though no apparent decrease in effort or cadence, second half mile dropped to around 4:45. Although I tried to pick it up in the first half of the second mile, pace only increased to 4:42 and I could pick it up any more without pushing harder than the workout called for. Anyway, I was able to keep the remaining half miles between 4:40 & 4:44, but I was starting feel a bit gassed mid-way through mile 3 so I ended the tempo run after 3 miles. Cool down was fine.