First 2 years, it depends on how strict your school is on attendance, but most schools are flexible enough for you to do it. Starting in clinical years (mid way through MS2 or more commonly MS3), it will be next to impossible to commit to regularly scheduled practices or games. If it is what you value and are willing to sacrifice on other fronts, there is absolutely time to play sports or pretty much do anything. But, you will have to be relatively flexible or do things that can be scheduled to match your clinical schedule rather than the other way around. For example, I rock climbed 3 days a week through medical school and played basketball 2-3 other days a week. It was a priority for me. But, I sometimes had to do those at odd hours, sometimes early morning, sometimes late at night, etc.