I'm working on a piece right now that is using extensive tremolo in the violins and basses. At the moment, those instruments play tremolo for around a minute leading into the rest of the piece. My question is: is there a limit to how long a real string section could play tremolo? I don't really have an idea as to how tiring that articulation could be for the musician, if at all. If anyone could enlighten me on this topic, I'd appreciate it. Thanks.