Contrary to popular belief, losing or even maintaining weight while training for a marathon can be incredibly difficult. Many marathoners either find they can’t quite achieve the weight loss they want, or, on the flipside, they’re able to lose weight, but at the cost of performance. It’s a hard balance to strike, but with the latest research it’s becoming much easier. The research in question revolves around the two concepts of Nutrition Periodization and Metabolic Efficiency Training. Together they increase the body's ability to use fat as fuel during exercise and thus optimize both body composition and performance.  Joining us in this episode is Bob Seebohar, the creator of these two concepts. Bob is a registered dietitian, exercise physiologist, NSCA Certified Strength and Conditioning Specialist, USA Triathlon Level III Elite Coach. He also traveled to the 2008 Summer Olympic Games as a sport dietitian for the US Olympic Team and the personal sport dietitian/exercise physiologist for the Olympic Triathlon Team. In this episode, Bob walks us through his findings on dietary efficiency and sheds some light on how best to achieve both the body composition and race day results you’re after. Oh and for those wondering, here’s a breakdown of the “alphabet soup” behind Bob’s name:   M.S. - Bob has three college degrees. His undergraduate is in Exercise and Sport Science. His two graduate/Master's degrees are in Health and Exercise Science, and Food Science and Human Nutrition. He successfully defended two theses during his graduate studies and knows his way around interpreting research and aligning it with real-life applications.   R.D. - Registered Dietitian. A college degree studying food science and human nutrition is required to be able to sit for this national examination. Of course, this is after successfully completing a 9 - 12-month nutrition internship after graduation.   C.S.S.D. - Board Certified Specialist in Sports Dietetics. A certification only given to Registered Dietitians who have years of experience working with athletes. A rigorous national examination must be passed and frequent continuing education credits upheld to acquire and maintain this certification.   C.S.C.S. - Certified Strength and Conditioning Specialist through the National Strength and Conditioning Association. Bob has worked as a trainer/strength coach since the mid 1990's and specializes in creating strength programs for endurance athletes.   M.E.T.S - Metabolic Efficiency Training Specialist. Bob explains this in his interview. :)   Questions Bob is asked: 5:06 Can you tell us about who you are and what you do? 7:45 What is Metabolic Efficiency Training and how does it relate to your concept of Nutrition Periodization? 11:50 How does Nutrition Periodization come into play with all the training variability runners experience? 14:34 How does Metabolic Efficiency Training work with runners who are trying to lose weight while increasing performance? 21:43 Why does eating become less intuitive to us over time? 24:40 How difficult is it for your athletes to change their nutrition philosophy? 27:45 How can runners adjust their macronutrient intake ratios to use fat as fuel more efficiently? 32:40 What is your opinion of Low-Fat, High-Carb and other ‘extreme’ diets? 39:01 Have you been able to get significant research yet into the role genetics plays with this? 40:39 Is the long-term goal to see where trends are and individualize athletes’ diets based on gender, genetics, etc.? 45:14 Has there been any research on Nutrition Periodization and how it relates to menstrual cycles and menopause? 47:06 What do you mean by the ‘Metabolic Efficiency Point’? 53:28 How would someone go about manipulating this efficiency point via nutrition? 56:54 Is it hard to do Metabolic Efficiency Training with Vegan, Vegetarian and Paleo diets? 1:00:50 Do you offer personal consultations?   Quotes by Bob: “Even for the leanest of the lean marathon runner, these elites that