Normally I would agree with this and say a mile is a mile. And I downloaded this image because I find it very motivational. But on a tempo run day I have to disagree.
Today I ran 7 miles. One mile warm up then 5 miles at an 8:00 min pace then a cool down mile. And let me tell you each mile was different.
The first mile felt like every first mile I run - a bit painful at first then it felt comfortable. Then at mile 2 I had to speed up and I wondered if I could do it for 5 miles. The next 3 miles were fine and I was just running in my groove. By my last tempo mile I was getting tired and had to put on my iPod to drown out my breathing. And by the last half of that mile I kept increasing my speed so I could just get it over with. Then my last mile was heaven. It felt good to slow it up a bit and just run it to the finish.