For what it's worth, I studied abroad for a semester and did absolutely nothing while I was there (besides travel and have fun). I'm applying this cycle and have 6 interviews so far and 1 acceptance, so I don't think it hurt me. Like hmockingbird said, I think study abroad is enough of an EC on its own. I did already have plenty of hours of research and clinical experience though, and was lucky to have positions that let me take a semester off then come back, so if you're short on hours it might be more of a concern. In contrast, one of my friends got a position at a research lab while we were abroad, so it's definitely doable if you want to although he had way less free time to go out and explore. Regardless, study abroad was the highlight of my college experience and you should definitely do it regardless of your med school apps!