This will make you think twice about dismissing the physical abilities of women.  Serena Williams If know Serena Williams, then you know better than to harbor any illusions that you can take on the top female tennis player even on your best day. Nicknamed by the media as the Queen of the Court, she has won 19 Grand Slam singles titles and 13 Grand Slam doubles titles as of May 2015. By the way, she can send the ball hurtling towards your face on the excess of 120 miles per hour on her serve. Ronda "Rowdy" Rousey  Former Olympic judo gold medalist Ronda 'Rowdy' Rousey has been dominating women's MMA for the past several years. She earned the nickname "The Arm Collector" for winning the majority of her fights via armbars. As of May 2015, no other female MMA has put up much of a challenge against Rousey, but some think that the next entry on this list just might give her trouble.  Cristiane 'Cyborg' Justmo Many believe that Cris Cyborg will give Rousey trouble and may even have an outside chance of beating her. While Rousey is an excellent grappler owing to her judo background, Cyborg is a more well-rounded fighter with excellent standup and groundwork skills. This means that just like Rousey, Cyborg can lay some serious beatdown on you. Missy Franklin So you think you are a good swimmer. Well, no matter how good you think you are, you'll very likely still be eating Missy Franklin's pool dust.  Missy is a four-time Olympic gold medalist and has also won a bunch of gold medals in the World Championships. Mirinda Carfae Do you think you can swim 2.4 miles, ride a bike for 115 miles, and still have enough gas to run for 26 miles? Mirinda Carfae certainly can and she proved that she can do it faster than any woman winning the Ironman World Championships women's division in 2010, 2013, an 2014. Rousey earned the nickname "The Arm Collector" because
She has been dominating women's MMA for the past few years She defeated most of the fighters with her armbars She can collect the strength of the other fighters with her armbars She has trouble in fighting without her armbars