Any good fitness plan needs cardio, but your well-honed Jazzercise kick-ball-change won’t help you as much as more basic cardio training.
Run for speed. Practice those sprints and get your mile run as fast as you can get it. Zombies aren’t fast, but if you aren’t either, you have a problem.
Cycle for endurance. Having strong cycling fitness and endurance can benefit in a number of ways. It’s much faster and easier on your joints than running. It gets you off dependency on gasoline for longer distance travel (gasoline is likely to be scarce in the days after the fall of mankind). And it builds your personal reserve of lightweight and comfortable cycling gear which may be difficult to obtain after zombies have taken over the local REI. Knowing how to travel 30 or more miles on a bicycle can mean the difference between being trapped in a dangerous urban area and finding a safer rural location.
Swim. Be able to swim. Zombies can’t. Not being able to swim eliminates one of your easiest escape routes from zombie hoards.
Any exercise that improves agility is great. Get yourself confident on a variety of terrains. Practice crossing rivers on fallen trees. Learn how to plant your feet solidly on rocky, gravelly, sandy and muddy terrain. And practice your linebacker moves for great dodging. Kickboxing class can help, so don’t slack on bobs or weaves!
Upper Body Strength
You’ll need to be ready for hand-to-hand combat. To help, work your upper body training. A few great upper body strength builders that also get you ready to defeat a zombie attack are activities like cutting wood (get great with your axe aim!), batting cage practice, and any sort of sword training. And don’t forget those pull-ups and push-ups for overall strength building.
Good Luck and Good Fitness!