Hit the Nature Trail for a Medicine Ball/Running Interval Workout. I ripped-off a medicine ball workout from Men's Health and peppered in some 400's for a nice little workout.
20 MB Circles/20 Ball Slams/20 Standing Russian Twists
20 Squat to Presses/20 MB Sit-ups/20 Rocky Solos/20 Toe Touchers
20 45 degree twists/20 diagonal touches
20:52 (1:41/1:45/1:45/1:41 splits for the 400's)
I forgot one of the exercises and didn't set-up my area before hand so the time is off. In the future, I'll break the exercises into sets of two and up the 400's to six and work up from a 10 lb medicine ball to 20lb.