Stretch reflex???

This is a bit of a theoretical question.
Does stretching (which causes inhibition of the muscle spindle) cause a decrease
in the stretch reflex (since the muscle spindle is what triggers the stretch

ive read that stretching immediately prior to activity will cause a short term
(approximately 5 minute)decrease in the stretch reflex.
But with long term increases of flexiblity (associated with consistently doing
stretching sessions aimed at specifically increasing flexibility) would this
associate with a general long term inhibition of the stretch reflex.

If so how do gymnast/sprinters etc utilize the stretch shortening cycle to there
advantage so effeciently while maintaining such high levels of flexibility?