Half of the gym will be set up with an equal number of hula hoops and poly spots. Spider man has to get from building to building (poly spot/hula hoop). When spider man gets from building to building he/she either has to horizontal jump to a hula hoop, or leap to a poly spot. If spiderman leaps/jumps and misses a building, than he/she has to slide all the way back to the starting point and try again.
Modification: If it is too easy, remove some of the poly spots and hula hoops.