in 1986 , a new zealander hackett popularized bungee as a commercialized sport of mass entertainment . this sport is very challenging . it is a test of people's psychological ability of endurance . especially when descending , as if they are watching a fast forward tape and when they bounce back , they sway around . the timid people will shrink back at the sight of it . even if they jump off , they find it hard to avoid screaming with closed eyes . no wonder people give the title ' brave ' to anyone who jumps off .