ABSTRACT
Endurance exercise sessions are defined as lasting more than 60 to 90 min; many endurance events may last from a few hours (marathon, Ironman, etc.) to a few days (orientation races, road race pro-cycling competitions such as Tour de France, Giro d’Italia, Race Across America, etc.), making it more difficult to achieve nutritional recommendations for these expedition-like competitions. During long-lasting moderate exercise, approximately equal amounts of fat and carbohydrate (CHO) are utilized by skeletal muscle to obtain energy; however, muscle glycogen reduction is associated with fatigue and reduced work capacity, as muscle tissue depends more on fat as an energy substrate in this situation, making blood glucose more important as energy fuel for contracting muscles in moderate to intense exercise (Genton et al. 2010; Melzer 2011; Melzer et al. 2013).
