Is it possible to complete both races if I've never done the 1/2 marathon before? I'm planning to run the 1/2 in 2012 and my mom is thinking of doing the Family 5K the same weekend. I know she'd feel more comfortable doing the 5K if I was doing it with her but she's concerned I won't have enough energy to finish the 1/2 if I do the 5K with her. Is it possible to do both if I've never done a 1/2 before?