Prepping for extreme survival situations often involves acquiring appropriate supplies and obtaining the training required to use them correctly. One often ignored subset of survival is the physical fitness of the prepper. How long would a 300 pound man with 35% body fat last if they were forced to bug out? When it comes to prepping, fitness is a critical element of the entire plan.
Realistically, you do not need to be at the fitness level of a professional athlete. In fact, many of the muscles needed for survival better fall in line with the work down by an Infantryman rather than a cross country runner. When it comes to extreme situations, you will be more likely carrying a pack and wearing boots rather than athletic shorts and field cleats.