Run

3.8mi in 29:10 (2.8 in 21:20, last mile in 7:50)
2 minutes rest, then:
as many rounds as possible without rest:
10 pushups, 10 crunches

I got through 5 without rest, then did one more set with a two second pause between each of the last five pushups (no rest for the crunches). So, 6 rounds total. I emphasized good form on my pushups, exploding up and going through the full range of motion with each rep. I stopped after 6 rounds so I wouldn't have to sacrafice form.