You don't go to medical school to get practical experience; you get practical experience so you know that medical school is right for you.
Students must have practical hands on experience in medicine so they can demonstrate and speak from example that they have a strong sense of what they are getting themselves into and why. During interviews, you can pull from these experiences to show your dedication to service and to the field you are pursuing.
Practical experience can come from being on the receiving end of medicine, getting treatments/surgeries, etc. They can also come from observing family members in health sciences or caring for family members. There are many ways to demonstrate that you are a person of service. We honestly believe that to be a health care provider you really have to be deeply involved in service to others now and have a track record that demonstrates this. Our most successful candidates have this kind of background.
It's nice to say you want to help people, but it is more important to be able to say what you did today to help someone. This service should be consistent and current. Volunteer work in junior high isn't enough. Volunteering in the hospital your first year of college probably isn't enough either. It is important to consider your competition when applying.
Note: Keep track of your practical experience hours religiously. Knowing exactly how many hours you have volunteered/worked in the field will help you later on with the application process, especially with schools that require a certain number of hours. Veterinary schools and physical therapy schools are especially strict about having lots of practical experience.