I'll admit that the game is already a bit unrealistic b/c of the jumps, but we are trying to keep it as realistic as possible, please refer to the chart.
Chart of realism:
Too realistic Right on Really unrealistic
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We are here Your ideas will bring us here
-Too realistic: you can run out of breath, you can fall and get injured, and jump 2 feet off the ground.
-Right on: You can keep running, falling just just slows you down a bit, and you can jump 4-5 feet.
-Really unrealistic: Jet packs, flying, cannons, vehicles.