The backswing phase is initiated when
the toe of the kicking leg lifts from the
ground. Hereafter the kicking leg moves
backwards (hip extension) with the hip
extending on average 29° resulting in a
large stretch of both the iliopsoas and
adductor muscles. There is, however, a large
variation of the degree of hip extension
and individual physical capacities between
football players, putting some players at
higher risk of injury than others. The hip
abducts slightly and both internal and
external rotation of the leg occurs during this
phase. The knee flexes and internally rotates
while the ankle everts. The backswing phase
continues until maximal hip extension of
the kicking leg, which occurs shortly after
the supporting leg strikes the ground.
During the backswing phase the upper
arm on the opposite side of the kicking
leg is lifted and moved backwards, which
effectively creates a tension arc of the
entire body to be released during following
phases. The tension arc has a crucial role in
effectively utilising the stretch-shortening
cycle necessary to maximise power output
of the kick. The backswing phase lasts
approximately 160 ms.