TY JOUR TI Stability of the equilibrium of the "athlete-barbell" system during execution of various types of the barbell squat KW powerlifting KW weightlifting KW barbell squats KW balance KW sports biomechanics JO Scientific notes of P. F. Lesgaft University AU Samsonova, A.V. AU Zaharov, F.E. AU Sagidullin, A.A. AU Samsonov, M.A. PY 2025 IS 0 PB National State University of Physical Education, Sports and Health named after P.F. Lesgaft