An athlete requires energy to fuel all physical actions and movements. This energy is supplied from the macronutrients and micronutrients consumed, and from the oxygen acquired through respiration. In their raw form, the food that provides the macronutrients and micronutrients, and the air that athletes breathe to acquire oxygen, cannot be used in their original state. These raw, unchanged fuel sources are called potential energy. There must be a change that occurs to convert the potential energy, into energy that can be used by the body (McArdle, Katch, & Katch, 2016).
The converted energy, which can be used by the body to fuel physical movement, is called kinetic energy. This process is collectively known as energy transfer. Through a variety of chemical actions and reactions, the body metabolizes the potential energy into kinetic energy, through two primary metabolic energy pathways. These two metabolic energy pathways are the aerobic system, which uses oxygen, and the anaerobic system, which does not use oxygen. This process of energy changing forms is described in the first law of thermodynamics. (McArdle et al., 2016).
The first law of thermodynamics refers to energy changing forms. Energy exists and does not disappear. It simply changes form, so that it can be utilized by different biological functions. In the case of human movement, energy transforms from chemical energy, to mechanical energy, ending with heat energy. This is also known as the conservation of energy. These complex chemical changes, concerning the energy’s form in the body, are known as biosynthesis (Kim & Roberts, 2015).
The body has a process which it uses to release energy and to store energy. The exergonic process releases energy to its surroundings, while the endergonic process stores energy. The energy that is released is known as free energy, and is available to be used in biological functions. These two processes often work together in a very complicated chemical state, to regulate and optimize the availability and use of free energy. Energy itself does not increase or decrease. However, the forms of energy that are available do change, as a result of many different chemical reactions (Kim & Roberts, 2015).
Unfortunately, for the athlete, these changes almost always lead to less kinetic energy available for physical activity. This concept is known as entropy, and it ties directly into the second law of thermodynamics. The second law of thermodynamics refers to the eventual degradation of potential energy, into kinetic or heat energy. This degradation decreases the capacity to perform physical activity (Kim & Roberts, 2015).
Fortunately, when one form of energy decreases, other forms increase. This cycle is continual in nature. The energy doesn’t disappear; it continues to change its form. At any given time, an athlete’s body is performing three types of biological work. These three types of work include mechanical, chemical, and transport. These types of work tie into energy transfer and the metabolic energy pathways. During physical activity and exercise, duration and intensity determine how and where, energy is being transferred and utilized. The aerobic and anaerobic energy pathways have specific functions, in relation to exercise (Chamari & Padulo, 2015).
The anaerobic energy pathway is utilized during short duration, high intensity events such as sprinting, powerlifting, and Olympic weightlifting. The anaerobic system actually has two main subsystems or pathways. The first is the adenosine triphosphate (ATP) and phosphocreatine (CrP) pathway or ATP-CP. This pathway provides the energy for approximately ten seconds. After ten seconds, the second pathway activates. This second pathway is known as the glycolytic pathway. This pathway provides energy for approximately ninety seconds. This is the approximate time window where the anaerobic pathway is thought to end (Chamari & Padulo, 2015).
After ninety seconds, the aerobic or oxidative phosphorylation pathway takes over. This pathway continues providing energy for long duration activities such as distance and endurance events. Within the first two minutes of exercise or physical exertion, the athlete has activated three different energy pathways, belonging to the anaerobic and aerobic systems. Also the three biological forms of work are all functioning to assist with the demands on the body. There are ongoing debates amongst researchers, concerning the exact timings and roles of the energy pathways (Chamari & Padulo, 2015).
Proper nutrition for an athlete is absolutely critical, in order to meet the high energy demands of athletic training. The correct caloric intake, combined with a proper macronutrient ratio is essential for an athlete to meet their needs and goals. The body uses carbohydrates for the bulk of its energy demands. Glucose and glycogen play crucial roles in energy transfer during anaerobic and aerobic metabolism (Liesa & Shirihai, 2013).
Fats come into play during longer duration aerobic events. When muscle and liver glycogen levels, and corresponding glucose levels decrease, more fats are used to sustain energy transfer. Fats transfer energy slower, and can only generate about half as much energy production as carbohydrates, in the same amount of time. When the activity reaches a long duration such as the end of a triathlon or marathon, the remaining macronutrient is called up. The last in line for energy transfer are proteins (Liesa & Shirihai, 2013).
When energy demands are very high, glycogen levels are very low, and fats are too slow during the transfer process, proteins are called upon to help out the team. The athlete does not want to be in this situation, where proteins are being called upon to sacrifice themselves, for energy production. Proteins are broken down into their amino acids through deamination, and other methods that make them suitable for energy transfer. This can cause a loss of lean body mass, and cause decreases in performance, with rising fatigue levels (Longland, Oikawa, Mitchell, Devries, & Phillips, 2016).
Overtraining is a viable threat for hard working athletes. But it can be avoided with proper rest, nutrition, and training. It is very important for an athlete to recover properly after each period of training. Athletes must replenish and maintain their hydration levels, electrolyte levels, and muscle and liver glycogen levels. Consuming the right amount of calories, with the correct ratio of carbohydrates, fats and proteins, is an important part of preventing overtraining. Poor nutrition and dehydration, combined with intense training, poor rest, and high stress levels can propel an otherwise healthy athlete, into the overtraining mode. By eating properly, athletes can maintain an anabolic state and reduce the catabolic effects of intensive training. Coaches need to ensure that their athletes are doing the right things, so that overtraining does not occur (Cadegiani & Kater, 2017).
Longland, T., Oikawa, S., Mitchell, C., Devries, M., & Phillips, S. (2016). Higher compared with lower dietary protein during an energy deficit, combined with intense exercise promotes greater lean mass gain and fat mass loss: a randomized trial. American Journal of Clinical Nutrition. Retrieved from http://ajcn.nutrition.org/content/103/3/738.short
Nutrient timing is very important for overall health, body composition, and athletic performance. Consuming the needed amount of calories, with the correct macronutrient ratio, at the proper time can provide the athlete with optimal results. There are three primary nutrient timing windows. These nutrient timing windows include pre-workout, post- workout, and the period of time until the next pre-workout window. Nutrient timing windows are also known as the energy phase, the anabolic phase, and the growth phase. These three phases essentially cover the twenty four hours of the day. The athlete has the additional challenge of mastering these nutrient timing windows. It is the nutrition plan that makes all of the athlete’s hard work pay off, in the gym, and on the playing field (McArdle, Katch, & Katch, 2016).
The pre-workout or energy phase is a critical window concerning nutrient timing. This is the phase that provides the athlete with optimal fuel for performance, during a game or training session. It is recommended that the energy phase meal be consumed immediately before and during training. This timing is commonly referred to as pre-workout and intra-workout. There are numerous research studies that have shown the positive benefits of this nutrient timing window. In addition to enhancing performance, the energy phase also limits the catabolic effects of intense physical exertion (Brown, Imthurn, & Ramsay, 2015).
While many studies show the positive effects of a variety of pre-workout nutrients, there is a common thread that appears to hold true. The main nutrients that make up the energy phase requirements are carbohydrates and proteins. The pre-workout and intra-workout meals should contain twenty to twenty six grams of high glycemic carbohydrates. There should also be five to six grams of whey protein. Additional recommended nutrients include magnesium, sodium, potassium, vitamin C, vitamin E, and leucine. For ease of consumption, most athletes make this meal in liquid form, as a drink or shake (Brown, Imthurn, & Ramsay, 2015).
The anabolic phase or post-workout window is the forty five minute time period immediately following training. This phase is also very important for the athlete. Hard, intense training leads to catabolic effects which can break down lean body mass, and increase fat storage. No athlete can afford to let this happen, if they want to be successful. Proper nutrition at this stage can reverse these catabolic effects, and turn it into an anabolic period of muscle sparing and protein synthesis (Sharp et al., 2017).
The nutrition profile for the post- workout meal contains forty to fifty grams of high glycemic carbohydrates, and thirteen to fifteen grams of whey protein. This is also normally consumed in liquid form. Recommended additional nutrients include vitamin C, vitamin E, leucine, and glutamine. High glycemic carbohydrates and whey protein are used, because they digest and metabolize faster than other forms (Sharp et al., 2017).
After the anabolic phase, the growth phase continues until the next energy phase. The goals of the growth phase are to build muscle, replenish glycogen stores, and to promote recovery. The growth phase is broken down into two sub-phases. The first sub-phase is the rapid segment, which lasts for the first several hours. The goal of this phase is to replenish glycogen stores. This is done by maximizing glucose uptake and insulin sensitivity. This phase also initiates recovery and muscle growth (Helms, Aragon, & Fitschen, 2014).
The next sub-phase is the sustained segment. This period lasts for approximately sixteen to eighteen hours following the rapid segment. The goal with this period of time is to increase muscle building with a positive nitrogen balance. The growth phase nutrition profile includes fourteen grams of faster digesting whey protein, two grams of slower digesting casein protein, and two to four grams of high glycemic carbohydrates. It is also recommended to include leucine, and glutamine to aid in recovery and muscle building. By following a disciplined nutrition window timing program, athletes can receive the proper nutrition necessary for optimal performance, muscle building, and recovery (Helms, Aragon, & Fitschen, 2014).
Skinny fat is alive and well in today's society. You can be thin and still have a lot of body fat. Your body fat percentage has nothing to do with how much you weigh on the scale.
Your total calorie intake per day and your macronutrient ratio of protein, fats and carbs determines whether or not you will make progress during your body transformation program.
Your performance during your workouts and your fitness level, directly correlates to how well you followed your nutrition plan that week. If you didn't eat well, don't expect to achieve great things during your workout. If you did eat good, your performance should reflect that.
People usually think they're eating much better than they really are and they usually over or under estimate their macronutrient ratio and calorie intake. That is why food journals do work and are helpful.
99% of the time, if you increase your protein intake, great things will happen.
Nutrition, hormone levels, stress, medications, sleep and water intake all have a tremendous impact on your results. Keep all of these variables in mind because exercise does not equal success alone.
Common issues with the plant based, vegan, or vegetarian diets include total protein intake, complete protein intake, iodine, zinc, selenium, iron, calcium, vitamins A, D, E and K (the fat-soluble vitamins) and B12 levels. If you are following one of these diet plans, make sure you are getting the macro and micro nutrients that you need.
The bottom line is that you need to eat the right amount, of the right foods, at the right times, to support your needs and goals.
Macronutrients are the body’s major fuel sources used to provide energy, and the raw materials to sustain, grow, and repair the body’s operating systems and infrastructure. The macronutrients consist of proteins, fats, and carbohydrates. Each macronutrient has specific roles and functions that help the body operate at, or near, optimal capacity. Carbohydrates serve four major roles. These roles include central nervous system fuel, primer for metabolism, sparing protein, and an energy source for the body (McArdle, Katch, & Katch, 2016).
Fats also serve four major roles. These roles include suppressing hunger, protection of vital organs and promoting thermal insulation, providing a transportation mechanism for fat soluble vitamins, and acting as a reserve source of energy. Proteins provide important support to the hormonal, transport, metabolic, and tissue synthesis and systems. Proteins provide amino acids, and contribute to cellular, muscular, skeletal, and numerous other internal systems. Together, the three macronutrients provide the body with all of its important needs, in order to operate in a healthy state (McArdle, Katch, & Katch, 2016).
Micronutrients consist of thirteen vitamins and twenty two minerals. Vitamins are categorized into water soluble and fat soluble groups. Each vitamin has specific functions, and all help to maintain the optimal physiological operations of the body. Minerals assist with cellular metabolism, bone and teeth formation, balancing acidity levels, neural functioning, muscle contractions, and heart rhythm (Ahmed, Ali, Islam, Hoque, Hasnat, & Nahar, 2016).
Minerals also assist in the operations of the immune system and other biochemical functions of the body. Both vitamins and minerals assist with antioxidant defense against free radicals and oxidative threats. Together, vitamins and minerals provide a wide variety of essential functions, for all major biological operations and systems of the body (Ahmed, Ali, Islam, Hoque, Hasnat, & Nahar, 2016).
Proteins, fats, and carbohydrates provide many important functions in the body, especially during exercise. Proteins are important for building lean body mass, which includes muscle tissue, connective tissue, and healthy bones. Proteins also help facilitate fat loss, or the loss of fat mass. In emergencies, proteins can be broken down to provide more glycogen to the body. Carbohydrates are the body’s main fuel source during exercise. When carbohydrate levels are sufficient, protein is spared during exercise (Helms, Zinn, Rowlands, & Brown, 2014).
When the body goes through the anaerobic phase, and begins the aerobic phase of exercise, after about two minutes, the carbohydrates become the main fuel. When glycogen stores begin declining after prolonged exercise, fatty acids are broken down into glycogen to sustain the body’s fuel needs. In dire cases of glycogen depletion, fats can break down into ketones to provide fuel. The three macronutrients work in concert to keep the body fueled and strong, throughout whatever stressors that one may face (Helms, Zinn, Rowlands, & Brown, 2014).
Vitamins and minerals are the micronutrients that support numerous chemical, biological, physiological, and metabolic actions, and systems within the body. During exercise the micronutrients play key roles in assisting with the break down and utilization of the macronutrients to provide fuel, and energy. They also assist with defense against free radical damage, muscular contractions, and thermoregulation. Micronutrients are extremely important during all catabolic and anabolic functions of the body. Not only do they provide vital functions in maintaining general health, they are critical components in numerous physiological activities during exercise (Pingitore, Pace, Lima, Mastorci, Quinones, Iervasi, & Vassalle, 2015).
Helms, E., Zinn, C., Rowlands, D., & Brown, S. (2014). A systematic review of dietary protein during caloric restriction in resistance trained lean athletes: A case for higher intakes. International Journal of Sport Nutrition and Exercise Metabolism. Retrieved from http://journals.humankinetics.com/doi/abs/10.1123/ijsnem.2013-0054