Erin Oprea is a former Marine of nine years, including two tours in Iraq. She lead the first all-female platoon attached to the infantry in a war zone and now is a trainer for over ten years with celebrity clients Carrie Underwood, LeeAnn Womack, Kellie Pickler, Jana Kramer and Jennifer Nettles, just to name a few. She is the author of The 4x4 Diet, which helps people focus their eating in four key areas and create workouts based on Tabata timing for great results. On today's episode of Bulletproof Radio, Dave and Erin talk about endurance training, high-intensity training, toxic foods, her work with celebrities, her experiences in Iraq, writing a recipe book and more. Enjoy the show!