4 miles-3x1600

Ran the first two intervals at an 8:45 pace with 200 metes recovery. A quarter of a mile into the third interval I got a horrible cramp in my back and had to walk for about 20 second to get it to go away, finished the interval (minus the 20 seconds) in 9:04. Still exhausted and a little crampy a couple of hours later. Hope it makes me faster!