Answer:
A trampoline spotter is someone who watches a trampolinist while they are performing or practicing. Trampoline spotters are usually used in competitive trampolining, standing on each side of the trampoline that is not protected by a spotting deck.
Trampoline spotters will watch the trampolinist perform, if the performance goes wrong and the trampolinist travels too close to the edge of the trampoline, the trampoline spotter will raise their arms to protect themselves and also to stop the trampolinist from falling off the trampoline, to do this they simply push the trampolinist back onto the trampoline.