Kris Gethin has established himself as one of the most versatile fitness entrepreneurs in the industry. As one of the world’s leading voices on bodybuilding and weightlifting, Sarah and Russ can learn some tips and tricks from Kris Gethin. His revolutionary training methods and techniques have shaped the workouts of millions of people worldwide; including a other pro bodybuilders and Sarah and Russ. They take the plank challenge and well Russ isn't working with a six pack for this one.