TY JOUR TI Thematic study of characteristics determining the effectiveness of the turn in backstroke swimming KW backstroke swimming KW turning technique KW kinematic characteristics JO Scientific notes of P. F. Lesgaft University AU Vinogradov, E.O. AU Krylov, A.I. PY 2026 IS 0 PB National State University of Physical Education, Sports and Health named after P.F. Lesgaft