Physical exercise of any kind is useful for psychological development. Your real workout doesn’t begin until you start to feel tired. Your discipline doesn’t emerge until you go to train when you feel like just sitting at home.
Revolutionary struggle is when there is no surging momentum, and you feel alone and feel like it’s pointless to confront the system , but you do it anyway. It is not in the victories; but in the moments of fear and depression and isolation, when you keep trying even when you don’t see any results. When you want to retreat and give up, and just live your life, but you ignore all of that and persevere.