Energy Balance
Adequate caloric intake yielding plenty of high energy nutrients to support energy demands is an absolute requisite for athletes to prevent diminished performance, and support training adaptations. It must be noted that caloric intakes and requirements for athletes are generally higher than those of general populations simply due to the volume and frequency in which these individuals train and complete. While general guidelines exist to help guide nutritional intakes for athletes, appropriate intakes should be customized to the individual’s goals, overall bodyweight and size, how frequently and/or the intensity they are practicing, training and competing in athletic competition. Considerations must also be made for athletes required to meet a specific weight prior to competition or who perhaps require additional conditioning and may need to cut excessive bodyfat levels. As a general rule of thumb, athletes participating in moderate to high intensity and volumes of training should aim to consume 40-70kcals/kg/day (Kerksick et al., 2018). Moderate levels of training being defined as a training frequency of 5-6 days per week for approximately 2-3 hours per day (Kerksick et al., 2018). An athlete participating in high intensity training is referenced as training at frequencies of 5-6 days per week with 1-2 workouts per day totaling 3-6 hours per day (Kerksick et al., 2018). This for example could represent athletes participating in two a day practices or even daily practices followed by team workouts later on in the day.
In addition to overall caloric intake, considerations must also be observed in regards to individual macronutrient distributions to optimize performance, recovery nutritional demands and needs and to avoid gastrointestinal discomfort during training. The macronutrients, as described in detail in the Nutrient Guide section, consist of the three energy yielding nutrients, proteins, carbohydrates and fats. Adequate carbohydrate consumption remains at the forefront of concern for athletes participating in team events or endurance-based sports as their bodies preferred quick and efficient energy source, therefore carbohydrate intake should be consumed at a rate such that muscle and liver glycogen stores are replenished, and enough carbohydrates are supplied to support energy requirements. Protein needs for athletes, much like carbohydrate needs, are higher than general population. Sufficient protein feedings will ensure a positive nitrogen balance, reduced catabolism and reduced muscle wasting (Kerksick et al., 2018).
Hydration Strategies
Just as important as optimal caloric intake, proper hydration strategies, more specifically reducing risks for dehydration, is a critical component to nutritional intervention planning for athletes. Maintaining hydration levels is key to sustaining performance, so athletes should pay special attention to their hydration needs. Interventional hydration strategies include weighing themselves if possible both prior to and at the completion of training. Weight loss due to sweating rates of 2% of total bodyweight can severely impair performance, while a 4% reduction can increase the likelihood of heat illness such as heat stroke and the possibility of death (Kerksick et al., 2018). Special consideration should be made and even greater focus placed on athletes participating in training or competition in hot or humid conditions as this will accelerate average sweat rates which typically range from 0.5-2.0L/ hour (Kerksick et al., 2018). An athlete’s primary goal for hydration strategies should be avoid dehydration by not waiting until they are experiencing symptoms of thirst to begin hydrating, and more importantly, hydrating enough both prior to training, during and even after to maintain their current total weight and avoid excessive drops in bodyweight due to fluid losses (Kerksick et al., 2018).
The table below lists the recommended fluid intake strategies for athletes:
Night before training
500mL water
Morning of training
500mL water
20-30 minutes preworkout
400mL – 600mL water
Intraworkout every 5-15 mins
12-16mL
Postworkout
3 cups of water for every pound lost due to sweating from training
(Kerksick et al., 2018)
Nutrient Timing
In order to optimize athletic performance, special care and consideration should be taken to not only ensure athletes are consuming adequate energy to support athletic endeavors and further recovery, but also to strategically plan the timing of consumption of certain nutrients. Prior to engaging in training sessions or athletic events, athletes should aim to consume a well-balanced meal rich in carbohydrates at a minimum of four to six hours prior to the event, this will ensure that nutrients are digested and assimilated into and reduce the likelihood of gastrointestinal distress (Kerksick et al., 2018). Four hours is what is required for consumed carbohydrates to go through the digestion process and into the blood stream to be assimilated to glycogen and stored in both hepatic and muscle tissue (Kerksick et al., 2018). In instances in which time constraints exist, limiting nutrient timing such as an athlete that wakes at 6am to practice at 7am, breaking necessary sleep cycles to eat 4-6 hours in advance may not be a feasible option. In this instance, a lighter snack consisting of primarily carbohydrates and protein would be the best option. Intra-workout nutrition should also be observed, and athletes should aim to consume glucose and/or electrolyte solutions during the session, especially if it is lasting longer than 90 minutes, or more importantly if the athlete is underneath his or her energy requirement needs for any reason or is training fasted (Kerksick et al., 2018). The addition of free form amino acids to a glucose/electrolyte solution during training may serve to be even more beneficial for a multitude of reasons (Kerksick et al., 2018). The addition of free form amino acids serves to increase amino acid availably during exercise to offset the catabolism of protein being induced by training, minimizing muscle damage and providing the body with amino acids and maximize muscle protein synthesis levels (Kerksick et al., 2018). Optimal intra-workout doses of glucose should fall between 30-60g of carbohydrate-electrolyte solution, with an optional added 10-12g of free form essential amino acid solution and sipped one every 5-15mins during training (Kerksick et al., 2018). The addition of added proteins around training or free form essential amino acids intra workout become more critical for athletes training in a glycogen depleted state.
Glycogen restoration and fluid rehydration are key strategies to optimize performance among athletes, however all of these strategies should be employed within the context of the athletes needs and be highly specific and customized to their individual goals and requirements. Therefore, for post workout nutrition, athletes should seek to consume a combination of both protein and carbohydrates within 30 minutes of training cessation, followed by a larger bolus meal with a higher distribution of carbohydrates within a two-hour mark of training cessation (Kerksick et al., 2018). It is recommended that athletes participating in multiple practices per day or athletic events per day which may require rapid glycogen replenishment to partake in an aggressive immediate post workout combination of high-quality protein in addition to high glycemic carbohydrates (Kerksick et al., 2018). Finally, the addition of caffeine at a dose of 3-8mg/kg with the high glycemic carbohydrates and protein has been shown to rapidly promote glycogen restoration (Kerksick et al., 2018). If an athlete is adequately fed and able to practice adherence of a well-timed and energy adequate pre-workout meal, then the post-workout replenishment may not be as necessary. The post workout refeeds are much more critical for individuals who are underfed or fasted prior to engaging in training (Kerksick et al., 2018).
Listed in the table below is a quick reference summary chart for nutrient timing recommendations for athletes:
Pre-workout
Pre-workout Meal: 4-6hrs prior to training/ practice or event
OR:
Pre-workout Snack: Or if training first thing in the AM semi fasted consisting of:
· 50g Carbohydrate
· 5-10g Protein
· 400mL – 600mL water/electrolyte solution
Intra workout
· 12oz – 15oz water solution base
· 30g – 60g glucose – sodium/electrolyte solution blend
· 300-600mg sodium per hour during prolonged sessions of training
· 10g – 12g Free Form Amino Acid Blend
Sipped on every 5 – 15mins during training
Post Workout
30 Min’s immediately post workout
· 3 cups of water for every pound lost due to sweating from training
· 3-8mg/kg Caffeine
· High glycemic carbs at 1.2g/kg/h
· Protein at a dose of 0.2-0.4g/kg/h
This strategy is employed for those athletes who require immediate glycogen re-synthesis.
(Kerksick et al., 2018)
Recovery Strategies
In addition to nutritional and in certain instances, dietary supplement protocols, various other strategies can also be employed by athletes to help facilitate recovery. Sleep hygiene, including the total duration and quality of an individual’s sleep cycle, is the most critical aspect for physiological recovery for high school athletes, but it is both often overlooked and neglected. The absence of sufficient sleep can impair the full athletic potential of an athlete (Knufinke, Nieuwenjuys, Geurts, Coenen, & Kompier, 2018). A number of factors athletes sleep hygiene including, unfavorable training schedules, late training times, general individual variances such as anxiety, and consumption of caffeinated beverages and supplements (Knufinke et al., 2018). Athletes experiencing sleep disturbances should aim to partake in routines which set them up for fewer sleep disturbances, as research has indicated a higher rate of sleep issues in direct correlation with specific daytime behaviors (Knufinke et al., 2018). Additional methods of recovery include stretching modalities, deep tissue massages, active recovery workouts, cold water immersions, low intensity cardiovascular training and contrast water therapy (Crowther, Sealey, Crowe, Edwards, & Halson, 2017). According to research most athletes note that stretching modalities yielded the most effective recovery method and determined that recovery strategies were subjective and based off of self-feelings following use of various recovery methods (Crowther et al., 2017).
Additional Resources for Athletes
Training in extreme temperatures or excessively hot and humid temperatures can create a number of concerns for athletes. If and when possible, athletes should be given sufficient time to acclimatize to training environments (Kerksick et al., 2018). An acclimatization period will encourage physiological adaptations that ultimately improve thermoregulation and also facilitate improved heat tolerance (Kerksick et al., 2018). Provided sufficient exposure, morphological and chemical adaptations occur which can reduce negative effects of heat stress such as increased physiological and cardiovascular strain and reduced aerobic performance (Periard, Racinais, & Sawka, 2015). Physiological adaptations include lower overall body temperatures, improved cellular protection, altered metabolism, improved skin blood flow and sweating (Periard, Racinais, & Sawka, 2015).
The allure of performing at a level far surpassing one’s own peers is one adolescent teens are often intrigued by. The use of performance-enhancing substances is a topic of concern as the increased availability and access to performance enhancing substances along with increased reports among pediatric populations (LaBotz & Griesemer, 2016). Despite the obvious detrimental effects these substances can have on a user’s health, it should be noted that in regard to adolescents, the benefits of PEDs were no greater than that observed from adolescents adhering to a structured training program and consuming adequate nutrition (LaBotz & Griesemer, 2016). A combination of maturation and increased endogenous hormone secretion by adolescents coupled with 8 – 20 weeks of structured training programming yielded 30% increases in strength which can contrast ergogenic effects from PED’s (LaBotz & Griesemer, 2016). In addition to negative health short- and long-term consequences PEDs, such as anabolic hormones, can have on systems of the body, especially the endocrine function of developing youth, PED’s can create negative sports experiences for athletes due to the moral dilemmas associated with cheating and an unfair playing field for PED users (LaBotz & Griesemer, 2016).
Conclusion
In conclusion, there are many factors that play into not only the athletic success of an athlete, but also the health of an athlete. Maintaining proper nutrition and hydration status are of the utmost importance, but other considerations need to be made for rest, recovery, sleep, and supplements. Supplements can benefit athletes if used properly but have the potential to ruin an athlete’s opportunities and affect health if used improperly or illegally. There are many helpful resources for athletes to engage in, but there are also many resources that can steer athletes down the wrong path. Always be sure to consult with a physician if thinking about using any supplements or changing dietary intake. Overall, keep in mind that each athlete’s body will have unique nutrient requirements and will adapt differently to training.
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