Things you need to know...
...about cross-country running:

- at least 2/3 of the distance to run will be up-hill
- being fit doesn't help if the temperature is around 30°C (~115°F) and the climate can only be described as "humiliatingly humid"
- your muscles won't be sore that night already; they'll wait until you're home and wanna go out to the next dance club/pub (option: until you have to climb stairs repeatedly)
- just when your muscles are close to being in a state of "alright" again, you'll have to do another cross-country run; this time, however, the distance to run is twice as long (you don't have to do it within a certain time-frame though, as a "compensation")
- on the second run, you'll get lost

This has been tested. Very much to my disliking. It was fun nevertheless...