https://community.usms.org/swimming/f/general/12646/no-propulsion-coming-from-backstroke-kickI've been learning to swim backstroke recently (I only swim freestyle). However, I have a problem: I don't know how to kick correctly. I already watched many videos on youtube about it, but I still can't do it. My knees are slightly straight (not bendingen-USTelligent Community 12