Groups of three stood on a pair of parallel wooden planks and had to work in unison to walk down and back .
Others stood in walking boots fixed atop a pair of sneakers to try walking while unable to physically feel the ground below .
Groups of three stood on a pair of parallel wooden planks and had to work in unison to walk down and back , while others stood in walking boots fixed atop a pair of sneakers to try walking while unable to physically feel the ground below .