Here’s why Ronda Rousey is good at armlocks. World Judo Champion AnnMaria DeMars teaches many important aspects of Juji Gatame. AnnMaria is Ronda Rousey’s mother and is the person who taught Ronda Juji Gatame. AnnMaria won many matches with Juji Gatame and offers some specific technical points that make a difference. As the great coach John Wooden said; “Small things make big things happen.”