Ronda Rousey is the most dominant athlete alive.

The 28-year-old has won every UFC fight she has fought, beating some of her opponents in less than a minute. In the process, she has elevated women's MMA and made it a key component of UFC — something that was hard to envision five years ago.

But before she became a crossover star, she was a regular 20-something struggling to figure out what to do after dedicating her life to making the Olympics.