<p>It depends on your goals. I knew I was going into academic medicine, so it was imperative that I start doing research ASAP. If this is your goal, you must start early. Applications can open mid Fall and can close as early as Jan. I did a wonderful research summer after freshman year. It literally changed my life. I don’t know why age should matter. I was 16 when I started college and nobody mentioned it. I was accepted at several programs that summer. Best of luck. </p>