Endurance sports and Nutrition are two fields that share the characteristic of being inexact and full of exceptions. With differences in genetics, tastes, and even cultures, it is impossible to give the same nutritional advice to everyone. Within endurance sports especially, individuals can have vastly different responses to the stresses involved with events that last anywhere from 2 to 24 hours, or even more. So when training for, and participating in, these types of events, each individual needs to find what works and what allows for his/her best performance.
According to an article published in the Sports Medicine Journal in 2014, there are specific stressors that trigger a response in the body that improves the oxidative energy system of the body. This makes that energy system more efficient by stimulating the production of mitochondria, which is where ATP, or the energy currency of the cell is produced. Additionally, the same stressors stimulate angiogenesis (blood vessel production), and the production of fat-oxidation proteins. These stressors include “Calcium and metabolic stress, in the form of heat, decreases in the adenosine triphosphate/adenosine diphosphate ratio, glycogen depletion, caloric restriction, and oxidative stress” (Baar). Most of these stressors occur naturally in endurance training. For instance, the decrease of the ATP/ADP ratio occurs as the muscles use up the available ATP, and metabolic stress begins to occur as soon as your body warms up. However, glycogen depletion and caloric restriction are two stressors that have to occur as well, but under specific, prescribed circumstances.
“Fat burning” is a phrase that is thrown around often in the fitness industry. It is important to understand this phrase in order to really understand what the goal is behind training your metabolism and reaching that prime level of efficiency. In the majority of cases, fat burning is used to refer to the continuing calorie burn that lasts a few hours after high intensity exercise. However, when referring to endurance sports, fat burning is associated with the oxidative energy system that uses the fat stored in the body’s muscles as primary fuel for creating ATP. This system, unlike the fat burning that occurs after high intensity exercise (more accurately called calorie burning), needs to be trained. So, what is the best way to train this system?
According to the same journal article mentioned above, starting certain “adaptive” workouts in a fasted, or calorically restricted state will help train this system to be more efficient. However, these workouts should be prescribed and mixed in with more “quality” sessions where the athlete fuels and replenishes calories properly. For the right adaptations to occur, these “adaptive” sessions must be done at low intensities and for a long period of time. By incorporating them into a training program correctly, an athlete can expect to have an “increase in mitochondria and blood vessels that is required to increase power/velocity at the lactate threshold” (Baar). Additionally, this type of training can affect the immune system, so if it is done too often the athlete can experience higher rates of infection and sickness.
While the details of an athlete’s nutritional plan must be adapted to his or her tastes, preferences, etc., there are principles that, if applied correctly, can help an athlete of any level increase their performance and their efficiency. Like anything else in this industry, it is important not to generalize because of the vast differences found in individuals. However, studies show that long, slow workouts with closely monitored nutritional intake and a carefully designed overall training plan lead to the development of a more efficient metabolism and better endurance sports performance.
Baar, Keith. "Nutrition and the Adaptation to Endurance Training." Sports Medicine 44.1 (2014): 5-12. Web. 28 Apr. 2015. <http://dx.doi.org/10.1007/s40279-014-0146-1>.