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Image source: DC Power Stilts via Flickr
See this short 3 min video and you'll understand. I believe that the main guy is using Powerisers stilts:
Jumping over stairs, fences, and other typical city obstacles would be impossible or energy draining for many of us, including well-conditioned athletes. But the guy from the video seems to do it effortlessly.
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Image source: Weirder the Better via Flickr
And it's not just for navigating city terrain. The video below is a man running around with an Air Trekker or Powerisers jumping stilts in a landscape suitable for off-roading, i.e. motorbikes, buggies, 4WDs, and such.
I can't pin down the fastest speed a human can achieve while wearing a pair of jumping stilts. The claims I've seen are around 17 mph (27 kph). Usain Bolt can reach a top speed of 27.79 mph.
Not a lot of video clips are out there on practical use of jumping stilts, at least not yet. But here's a funny one on how to use jumping stilts to rob a bank. Of course, I don't condone robbing a bank or committing any criminal acts with these, but what's interesting from the video is the concept of how one could outrun and outmanuever live human chasers. Slow zombies should be much easier to get away from.
Obviously there's a learning curve as shown by the following video.
There are also weight limits. For example, the Air-Trekker Jumping Stilts CZ90 Adult Edition is rated for 197-218 lbs (89-99 kg). And the Poweriser Jumping Stilt Advanced is rated for 198-266 lbs (90-120 kg).
Hence, from Season 2 of The Walking Dead, Shane should be able to use a pair of these, while Otis would have been shit out of luck.
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Image source: ap. via Flickr
I would like to see Glenn running around Atlanta with a pair of jumping stilts and getting away from zombies to safety. He's the right character for something like these.