想請問各位，有時會見到d師兄用啞鈴推膊時，會用一張低靠背既凳，
背部成弧形向後彎，只用靠背既頂部頂著上背，
咁既準備動作有咩好處呢？因與我所知既腰背要直貼凳肯，有著好明顯既分別！

i think this exercise should be contraindicated if those ching is arch their back
i personally like standing shoulder press cuz it causes less lower back pain to me