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Here, the arms are stretched UP and then only at the very top of the bounce is the tuck shape made.
On the descent the arms are brought back to the sides for the landing.
In this video there is a bit too much ‘lean forwards’ of the upper body in the tuck shape. The knees should come up to the chest more rather than leaning forwards so much, although this will happen to an extent.
Safety is the most important thing to get right when trampolining
especially when learning new moves. Read more on the
trampoline safety page.