In the mid-'70s was a Russian LJer Aleksey Pereverzyev PB 8/21
While Igor Ter-Ovanesyan was his coach.
They conducted experiments to create a new style in the long jump,
including Alex jumped "forward flip".
Moreover, in training, he jumped over 8.00m.
It has not been further development because the federation T&F URS found this method of jumping very dangerous and forbidden to use it in the future.
An interesting fact is that throughout his career, and to this day, TER, in his interviews is always returned to this subject and believes that progress results in the long jump is associated with a change of style and technique LJ.