inthe last 3 weeks i've been regarding that people in the gym hold the bars and barbells in a different way than mine (which is excactly like holding a dummbbells:4 fingers on one side and biggest finger on the other side).Actually they hold them with all fingers on one side.Is this right to do?Is it recommended?Does it help concentrate the movement on the muscle?Is this made with dummbbles too?Are there special muscles that you have to hold the bar like how they do????THANKS