COMPARISON OF BUNGEE-AIDED AND FREE-BOUNCING ACCELERATIONS ON TRAMPOLINE

Abstract

Trampolines remain the single best apparatus for the training of aerial acrobatics skills.  Trampoline use has led to catastrophic injuries from poor landings.  Passive injury prevention countermeasures such as specialized matting have been largely ineffective.  Active injury countermeasures such as hand spotting, “throw-in” mats, and overhead spotting rigs provide the most effective methods.  The recent addition of several bungee cords between the ropes and the gymnast’s spotting harness has resulted in altered teaching and coaching of trampoline-related acrobatics.  Bungee cords have eliminated the need for a coach/spotter to manage the ropes during skill learning.  The purpose of this study was to assess the influence of the addition of bungee cords with a traditional rope-based overhead spotting rig.  There is a paucity of any research involving trampoline injury countermeasures.  Ten experienced trampoline acrobatic athletes (5 males, 5 females) from the U.S. Ski and Snowboard Association Aerials National Team performed 10 bounces as high as they could control.  A triaxial accelerometer (200 Hz) characterized 10 bungee cord aided bounces and 10 free-bounces on a trampoline from each athlete.  Bed contact times, peak accelerations, and average accelerations were obtained.  The results supported our hypotheses that the bungee-aided bounces achieved only 40% (average) to 70% (peak) of the free-bouncing accelerations (all ρ < 0.001 and all ƞ2partial >0.092).  The bed contact time was approximately 65% longer during the bungee-aided bounces (ρ < 0.001).  Bungee cords may reduce the harshness of landings on trampoline.