Supplementation for Sports Performance – Controlling your Pathways

By Matt Van Dyke, Cal Dietz, and Zac Brouillette

It is commonly understood athletes involved in explosive competition events must have the goals of increasing muscle mass and maintaining explosiveness while reducing unnecessary body fat as these are key factors in improving performance. The nutritional tactics used must create an environment specific to the desired adaptation of training. Adaptation goals will typically fall under one of two categories. The first being to increase muscle mass, and the second to increasing the rate of fat usage for energy, leading to a reduction in fat mass. The training completed, dietary intake, and supplements consumed by athletes must be in proper alignment with each other and work towards the same adaptation goal. When these three factors, training, nutrition, and supplements, function towards the same adaptation goal, that desired adaptation will be realized to a greater extent, leading to maximized performance.

For the sake of this article, these adaptations systems of the body will be broken down into two separate pathways. The mTOR pathway, and the AMPK pathway. The mTOR pathway is responsible for protein synthesis and has an anabolic effect on the body. If you are attempting to increase lean muscle mass this pathway is an important aspect in accomplishing that goal. The AMPK pathway works in the exact opposite of mTOR, and occurs when the body is utilizing energy. The AMPK pathway is activated with decreased ATP levels, which are used for energy, and will be used to increase lipolysis, or the burning of fat. It is important to understand that these two pathways, mTOR and AMPK, cannot be activated simultaneously. Knowing that these pathways are opposites, and cannot be activated at the same time, along with the knowledge and methods to activate each pathway, allows for coaches and athletes to shift their training, nutritional, and supplemental strategies towards the pathway of their desired training effect.

The mTOR and AMPK pathways are a constant balancing act that a coach and athlete must focus on in great detail to achieve optimal adaptations. The key to reaching the potential desired adaptations of increased muscle mass, maintained explosiveness, and reduced unnecessary body fat is to shift the body, using proper nutritional tactics. Nutrition tactics will create the environment needed for each of these individual adaptations.

Keeping it Simple

A vital aspect of adaptation is to keep supplementation simple and minimal. Ensure the body is receiving the needed materials for the desired adaptation, and that adaptation only. The simplest example of this is if a coach is training an athlete with a program to decrease body fat, the coach will not supplement this athlete in a manner that will activate the mTOR pathway. The goal, in this scenario, would be to keep the AMPK pathway activated for as long as possible. The specific methods to apply this will be covered in greater detail in a later section. If this model of simplicity is not followed, the consumed supplements may cause the body to attempt to adapt in both directions, and end up, in a worst case scenario, not gaining any adaptations. A simple example of this can come from the weight room. If a performance coach attempts to train multiple qualities simultaneously, the body doesn’t know which adaptation to improve because it is being pulled in too many directions.

Pre-workouts used by athletes are a prime example of simplicity in supplementation being overlooked. These pre-workouts have the ability to blunt the adaptive process as they contain many different substances that may conflict with each other in their desired effects. Many times the ingredients list on these supplements can reach the teens and even into the twenties in their number of ingredients. With this many substances being absorbed at once, the organism becomes confused in what it is supposed to do, as each chemical has a different effect on the body. Two simple, and unnecessary substances found in pre-workouts are caffeine and arginine. Caffeine influences the AMPK pathway by increasing lipolysis, which increases the ability to use fat as an energy source. However, it should not be used habitually as an athlete has the ability to become accustomed to its effects after prolonged use. This leads to a greater amount of this stimulant needed in order to reach the effects seen in early supplementation. If a benefit is seen from caffeine, use it solely for competition days, but be sure to test it out a few times before doing so. This decreases the likelihood of a bad reaction and can assist in improving performance. Arginine is another substance found in many pre-workout supplements, along with its claim to increase vasodilation. Arginine is a pre-cursor to nitric oxide, which is a one factor in vasodilation, or the widening of blood vessels. The thought process is correct in supplementing with arginine, however, arginine has a relatively small effect on vasodilation when consumed orally. Another issue with using this supplement is that vasodilation already occurs during exercise, and blood flow is not the limiting factor of muscle performance.

mTOR Pathway

Muscle contraction is a stimulator for the mTOR pathway, however, building explosive muscle ultimately relies on creating the proper environment within the body and muscles that permits growth and adaptation. Creating this environment, when broken down simply, requires energy (ATP), protein, specifically amino acid availability, and the activation of the mTOR pathway. When one of these steps is missing, building muscle is not a possibility and training time is wasted. Once these steps are realized and implemented properly, the focus must shift, more specifically, to the rate-limiting step in the muscle building process. The rate-limiting step can occur at any point along the muscle building continuum, from transcription, to translation, to the building of structures with the use of amino acids. Once this rate-limiting step is identified, it can be corrected, and then a new rate-limiting step can be identified. The improper daily supplementation leads to the inactivation of the mTOR pathway as the rate-limiting step for many athletes.

An athlete must understand that it takes energy for the body to build muscle. If the proper nutrient and supplement tactics are not followed strategically, there will not be enough energy for this anabolic mTOR pathway to remain activated. Knowing energy is a requirement in order for mTOR to be activated and build muscle, it then makes sense that there is a transition period from a catabolic state (AMPK pathway), to an anabolic state (mTOR pathway) once training has been completed. Your body needs time to replenish ATP near resting levels before it can begin to shift to building muscle. The reduction of this transition time should be the goal of athletes attempting to maximize their muscle building capabilities. Simply put, spend more time building rather than breaking down. The use of carbohydrates, specifically high-glycemic carbohydrates that are rapidly absorbed, can reduce this transition time and ultimately lead to a longer time spent in the anabolic phase. A detailed article explaining nutrient timing post-training can be found in this post, Nutrient Timing for Proper Recovery.

Protein availability within the body is the second step in this muscle building process. Athletes and coaches must understand there is no pool of amino acids stored in the body just waiting to be used. Protein supplementation is all about the proper timing of intake, along with the correct form of protein consumption. Whey protein is a great source of protein as half of it is made up of essential amino acids, or the amino acids the body cannot synthesize on its own. Whey protein also contains a higher amount of branch chain amino acids, or BCAA’s, these BCAA’s include leucine, isoleucine, and valine. BCAA’s are a key ingredient in this process as they are not required to pass through the liver before being utilized by the body, which means faster availability for the building muscles.

While protein supplementation timing is crucial for explosive muscle development, athletes should understand the amount of protein their body needs. The body can only utilize around 10 grams of essential amino acids from 20 grams of whey protein at a time. After this level of intake is reached, supplementing with more protein is useless and will lead to protein being used as an expensive fuel by the body. For this reason, the timing or “pulsing” of protein supplementation plays an important role in the continued activation of the mTOR pathway. Understanding the mTOR pathway requires the use of energy, along with the transition time post-training from catabolic to anabolic, and the muscle-protein saturation effects, athletes can properly “pulse” their protein intake. Consuming 20-25 grams of whey protein between 30 minutes and one hour post-training is a great way to jump start the anabolic process, this time allows ATP levels to be replenished. Supplementation should continue with 20-25 grams of whey protein every 3 hours. This ensures muscles stay saturated and with the amino acids needed to continue building muscle, without the burning of protein as an energy substrate. Ultimately, this program would have 3 protein doses post-training, all being 20-25 grams in size. The first occurring 30 min post-training, the second around 3 hours, with the final dose being taken about 6 hours post-training.

AMPK Pathway

AMPK is an enzyme that is activated during times of energy depletion, such as those seen during strenuous training and practices. This energy usage leads to a decrease in ATP levels and an increase in AMP levels within the body. This pathway, when activated, mobilizes energy substrates stored within the body in order to sustain performance. AMPK also functions to block the mTOR pathway, as mTOR requires the further use of ATP, or energy, which is exactly what the body is avoiding at this time of increased fatigue. AMPK also improves insulin sensitivity and increases mitochondrial density when activated, which leads to a more efficient utilization of fat for energy during training.

As an explosive athlete, the “switching on” of AMPK must be done methodically. Turning on this pathway continually, when programmed incorrectly, will lead to aerobic adaptations, which can lead to a decrease in explosive performance. However, there are three routes available to activate AMPK, while preventing an aerobic shift of explosive athletes. These three methods to keep explosive power while increasing fat burning capabilities include AMPK activators, intermittent fasting, and high-intensity interval training (HIIT).

AMPK activators are substances, when consumed, lead to a slight stress response within the body. This stress response activates many pathways, one of which is AMPK. By activating this pathway using activators, athletes can increase mitochondrial biogenesis and achieve more efficient fat loss, while keeping their type II, explosive muscle fibers unaffected. Examples of these AMPK activators include green coffee bean, green tea, and resveratrol, along with many more. It is important to realize that more is not always better in supplementation, and that these substances are toxic to the body at high doses, yet assistive at stressing the body in smaller doses.

Intermittent Fasting is another method to activate the AMPK pathway. Restricting caloric intake prior to HIIT increases the amount of fat utilized as an energy substrate, particularly during recovery. Avoiding consumption of calories, particularly carbohydrates, up to two hours post-training will further enhance this fat burning process. Carbohydrates should be avoided prior to, during, and post-training when the goal of an athlete is to decrease body fat. Carbohydrates provide ATP to the body rapidly, meaning the body does not have to produce more mitochondria in order to replenish ATP levels. The mitochondria are a site of fat breakdown within the body, with fewer mitochondria in the body, less fat can be used as an energy source. A half day of fasting, up to 2-3 days per week, can be used to activate the AMPK pathway as well. This will increase the mobilization of fat used as energy within the body. It is important to ensure enough carbohydrates are being consumed throughout the day in order to support training. For this reason, the timing of nutrient intake plays a pivotal role in which pathway, AMPK or mTOR, is activated.

HIIT is one of, if not the, most effective means of increasing mitochondrial production while also maintaining the explosiveness of trained athletes. This low-volume, high-intensity exercise method is much easier on an athlete’s body, particularly their joints, than long-slow aerobic exercise, while also being more specific to an explosive athlete’s metabolic and neuromuscular demands of competition. All of this is accomplished by HIIT programming, all while requiring less time than the long-slow aerobic training protocols. Proper timing of nutrients is an important aspect of this fat-burning training and must always be considered. As discussed above, carbohydrate consumption will blunt the AMPK response and should only be used with appropriate timing. In order to maximize the training effects of HIIT, avoid consuming calories for up to an hour prior to training, especially carbohydrates, during the workout, and for up to two hours post-training. These recommendations will increase the AMPK pathway throughout training and keep it elevated post-training as well, leading to increase fat burning.

These three methods to increase the activation of the AMPK pathway can be used simultaneously when fat loss is the goal of training. HIIT training is the fundamental aspect of this model, especially for athletes in explosive events. The other two factors can be built around this training method and rely on proper nutrient timing in order to maintain AMPK pathway activation. Once the time of a HIIT program is set, caloric intake, especially carbohydrates, can be reduced and manipulated. An AMPK activator can also be added to post-training supplementation to increase the activity of the AMPK pathway, leading to further mitochondrial production and increased fat burning.

Anti Anti-Oxidants

Another area of interest in regards to nutrition and supplementation are anti-oxidants, which inhibit reactive oxygen species (ROS), or free radicals. ROS are produced during muscle contraction and can lead to the damage of protein structure DNA, rendering them useless as building blocks for muscle and can potentially lead to cell death. In the most basic explanation, anti-oxidant supplements, such as vitamin C and vitamin E, inhibit the ROS produced during training from causing damage to the DNA of cells. On the surface, a coach would be under the assumption that the use of anti-oxidants should be a daily aspect of supplementation in order to prevent damage to cells. However, the generalized use of anti-oxidants in an attempt to ROS produced during training is another example of improper supplementation. In reality the ROS produced by training are used by the body for adaptation, they are a stressor. These ROS can function in the same way strength training stresses the body, and ultimately leads to improved strength. If the body is never stressed, it never has to adapt, if it never adapts, no performance increases are realized. Anti-oxidant supplements lower the levels of ROS, ultimately leading to less stress being placed on the athlete’s body. If the ROS levels drop below the signaling zone due to the intake of anti-oxidants, smaller adaptations within the organism will be seen from training. A simple example of this necessary stress within the body is the law of natural selection, the strongest will survive. If the body experiences these stressors to the maximum levels produced from training, re-building of a stronger organism will be the outcome of proper training and this recovery. It is important to note that this method should be followed along with a properly periodized training protocol. Controlling the stressors of training is a vital aspect of this supplementation technique.

The use of anti-oxidants must be periodized within a training cycle. Just as an annual training cycle works through its proper progression, the use of these supplements must do the same. Off-season training versus in-season competition are two simple examples of how to periodize the supplementation of anti-oxidants into a training program properly. During off-season training, the goal is to prepare athletes for the upcoming season by stressing them maximally. It is at this time the majority of adaptations are realized. This is a period of time where athletes are encouraged to avoid excessive intakes of anti-oxidants. Many foods are already fortified with these substances, so it is our goal, as coaches, to attempting to prevent even greater amounts from being consumed, particularly in a high-dosage, post-training form. However, during the competition season, this thought process changes. The use of anti-oxidants to reduce damage and enhance recovery is an imperative aspect of performance, especially for the athletes that participate in multiple games in a short time frame. The use of these supplements will not continue to improve adaptations during the competition season, however their use will allow athletes to compete fully recovered, leading to consistently improved performance, particularly at the end of a long competition period. Once again, the specific goal of training along with the time of year, within the competition calendar, must be considered when deciding on the implementation of these anti-oxidants. 


Maximizing Your Pathways


The knowledge of these two pathways, mTOR and AMPK, allows coaches to program to the annual competition calendar, along with the needs of each individual athlete. The activation of the mTOR pathway post-training relies heavily on the ability of the body to resynthesize ATP, as this pathway requires energy in order to function properly. Training to improve the ability of resynthesizing ATP, particularly through the aerobic system, leads to a smaller transition time from AMPK to mTOR post-training. Shrinking the time spent in AMPK while increasing the amount of time spent with mTOR activated. This will lead to increased explosive muscle building within the body when proper nutrition tactics, as described above, are utilized. If the goal is to reduce body fat while maintaining explosiveness, AMPK activation will be the goal. The three ways to increase this fat burning pathway is to complete HIIT, use AMPK activators, and the use of intermittent fasting. Ultimately it comes down to determining the goal adaptation of training, and then implementing proper nutrition to achieve that adaptation.

It is important to understand that these two pathways have been over simplified in this article in order to improve basic understanding. The mTOR and AMPK pathways function most like a great soup recipe. You have your main components of the recipe, which in this case is the energy substrates carbohydrate and protein. The mTOR pathway requires energy, which is used by the body to begin the building process, while the AMPK pathway uses energy previously stored to increase breakdown. After the main components, of each individual pathway, have been properly placed into your soup recipe, the remaining “ingredients” function as flavor enhancers. These enhancers work to continually improve the overall “taste” or effectiveness of the individual pathway you desire to activate.