Fats vs. Carbs    &    Energy Storage       1 gram of Carbs (glycogen)    =    about 4 Kcal of energy   - a short term rapid energy source                                                                                                                         (sprint events)       1 gram of Fats                             =    about 9 kcal of energy   - a long term energy source                                                                                                                         (endurance events - marathons)           Average human contains about 0.5 Kg of stored glycogen  =      2,000  Kcal of energy                                                     and about 16 Kg of body fat                   =  144,000  Kcal                              to carry the same amount of energy [144,000 Kcal] as carbs                                 we would have to store 36 Kg [79.4 lb] more of glycogen                            to loose 1 Kg of body fat means you need to burn lots of calories.      back