There is a word «разбежка» - break off (mainly in aviation). May be you saw the combination this word with preposition «при». For example: При разбежке самолёт набрал скорость взлёта – During break off the plan had got take-off speed. And yet it is in sport: jumping, triple jumping etc. I’ve noted your question first accidently. I am sure you will get a lot of answers, cowboy! Good luck!