Kevin Hart & Serena Williams Create "The Hart Serena" Workout

There's no doubt that Kevin Hart and Serena Williams are both the very best at what they do. Their unrivaled determination to succeed and constantly improve has allowed them to reach the pinnacle of their respective fields, and bring joy to those watching them perform on the grandest of stages and tennis courts. With a shared passion for physical fitness, Nike gave the unlikely training duo an opportunity to create a partner workout for its new Nike+ Training Club app. Check out the hilarious cl...