Tip 52: Go by car

All good cross training involves something that will stress different muscles while putting pressure on your cardio-vascular system.
I recommend Punt Rd traffic.
Your heart rate will soar like a 12 per cent climb, and your fellow traffic-makers will see you engage in serious verbal gymnastics as you seek out the one foulest word that encapsulates your feelings for them.

BONUS TIP:
Deploy a variety of obscenities to work on your lip and tongue muscles - if everyone in your way is just a "fuck-wit", you're not going to get that all-over-toned look that really shows off your mouth.