Serena Williams’ Training Secrets: Big X Drill

X Marks the spot! Let Mackie show you some of the super secret moves that Serena Williams uses to become an all-time great.

Check out Mackie’s site to read more about the technique behind the exercises. Stay tuned to WWLTV every Wednesday to see more workouts you can do at home.

Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube.