Sports Nutrition

As the science behind nutrition and athletic performance continues to be investigated, the importance of what athletes are eating shows to have an increased impact on their sport’s performance.  Water is one of the most important nutrients an athlete needs as hydration status has a distinct influence on performance.  This goes for any sport, under any conditions.  Basketball is a unique sport due to the fact it combines the endurance to run up and down the court for a full quarter, as well as the speed, quickness, and agility needed during one-on-one plays.  Basketball is also a very long season, which takes place during the colder winter months.  This could give the players the need for specific nutrients that could potentially become depleted from the increased training and decreased exposure to sunlight.  With that said, the increased stigma that supplements are needed for athletes, is something that needs to be addressed.  Although it is safe to say athletes expending a much greater energy load than the average person needs increased energy, it is important to know which macronutrients will help fuel workouts.  Along with these macronutrients, it is important to understand when they should be consumed, as the research in nutrient timing proves to help enhance athletic performance.

Although basketball is not played outside in the heat, gyms can become very humid and therefore increase the athletes sweat rate.  Becoming dehydrated can not only cause athletes to become dizzy, thirsty, fatigued, and weak but these symptoms can drastically decrease the athletes performance and put them at serious risk of having abnormal breathing and possibly fainting (1).  The Academy of Nutrition and Dietetics explains how athletes should consume about 5- 7 mL/kg body weight of water at least 4 hours prior to exercise.  During exercise they explain that the hydration goal is to replace lost fluids through sweating, which can range from as little as 0.3 to as much as 2.4 liters per hour.  Since it may be unrealistic to meet these goals during exercise, it is important to fuel up on water post exercise in order to replenish the lost fluids.  The Academy recommends drinking at least 16- 24oz. of fluid for every pound of body weight lost during exercise (2).  Unfortunately, water is not the only substance lost through sweat, most commonly we can associate sodium losses as well.  It is important to replenish electrolytes in addition to water during and after exercise.  Carbohydrates are also commonly needed as hypoglycemia can occur, but that will be discussed in further detail later.  Knowing that electrolytes, carbohydrates and water all need to be supplemented during exercise led to the creation of a glucose electrolyte solution, which is known as Gatorade to most.   In the book Nutrition for Health, Fitness and Sport they claim that using an aide like this can provide adequate hydration, reduce cardiovascular strain, enhance performance, and prevent some heat illnesses (3).

As mentioned before, basketball requires endurance training in order for the players to keep moving for an extended period of time.  But at the same time, resistance training to improve speed, quickness and agility is essential during defense, one-on-one plays to the net, fast breaks and jumping for rebounds.  With that said, there needs to be a happy medium reached between the nutrient recommendations for endurance athletes verses the nutrient recommendations required for strength or resistance athletes.  The biggest difference in the diet would come in protein.  The Academy of Nutrition and Dietetics explains that power athletes need a bit more protein than the endurance athlete as they recommend 1.2- 1.7g/kg a day for power athletes and 1.2-1.4g/kg a day for endurance athletes (2).  Another subject brought up for athletes who must have both endurance and strength training is knowing the appropriate weight to be as well as the proper body composition to have.  Body weight influences the speed, endurance and power of an athlete while body composition can affect the athlete’s strength, agility and appearance (2).  The athlete needs to know what weight and body composition they preform their best at and work to maintain that body.

Basketball is a fairly long season compared to some other sports’ seasons.  Because of this, the athletes can have certain nutrient stores deplete from the rapid turnover and loss of micronutrients from the body.  Athletes may require a greater amount of micronutrients to ensure the building, repair and maintenance of lean body mass is stable (2).  The Academy of Nutrition and Dietetics recommends several vitamins and minerals that may need to be looked at for athletes.  First, the B vitamins have two major functions directly related to exercise including energy production and the production of red blood cells which is essential for protein synthesis and tissue repair (2).  If the athlete is a vegetarian or simply knows B- vitamins are missing from their diet, this could be a very beneficial supplement to add.  The antioxidant vitamins C and E have been linked to help improve physical performance and may also be beneficial to supplement if not regularly included in the diet (2).  When looking at minerals, the obvious are the electrolytes: sodium, chloride and potassium, which were discussed briefly with the importance of hydration.  However, zinc plays an important role in growth, building and repair of muscle tissue as well as energy production therefore, intake should be assessed to ensure the athlete is consuming enough.  The tolerable upper limit for zinc is 40mg (3).  Iron is also an important nutrient for athletes, especially endurance athletes as it can help increase the oxygen carrying capacity.  The Academy states that iron needs can increase by approximately 70% for endurance athletes (2).

Since basketball season is in the winter, the lack of sunlight may result in slight vitamin D deficiencies if the athletes are not consuming fortified foods.  Vitamin D is required for adequate calcium absorption, promotion of bone health, and it regulates the development of skeletal muscle. Athletes may benefit from adding a vitamin D supplement.  The Academy of Nutrition and Dietetics recommendations 1,500 mg elemental calcium and 400 to 800 IU of vitamin D per day (2).

Although some vitamin supplements may be beneficial from the evidence listed previously, the controversy of protein powders and ergogenic aids continues to be debated and continues to be experimented with by athletes.  The amount of supplements on shelves are endless, but some of the most commonly used by athletes are creatine, caffeine, whey protein, and branched chain amino acids such as leucine.  The Academy claims that creatine has shown to be effective in male athletes primarily during sprinting and weight lifting, not as much for endurance athletes.  It is still being debated but currently is considered safe for athletes (2).  Caffeine appears to be used so frequently because it is one of the legal ergogenic aids allowed in organized sports within certain limits.  Claims of increased fat burning and protection of carbohydrate stores have been made, however, does not necessarily appear to be correct during exercise.  Caffeine does however, increase alertness and stimulates the central nervous system (8).    Protein powders are no less, nor no more beneficial than consuming protein from foods according to the Academy of Nutrition and Dietetics (2).  The branched chain amino acid claims fatigue will be delayed and it will boost the immune system.  BCAA do provide fuel for endurance activity but they have not been shown to delay fatigue.  As far as the immune system support goes, it is still being researched however, it appears to be promising (8).  All supplements and ergogenic aids for sports performance are still being researched and are still a controversial issue.  In the end it is important to read labels to ensure the product is safe as well as legal for the athlete to use.

Something I believe is very hard for an athlete to do is to determine the appropriate amount of energy that is required for them.  Some may consume too little and feel fatigued during exercise, which will result in them performing subpar.  Others may consume too much which could result in an increase in body weight, a change in body composition, and GI stress from delayed gastric emptying or food in their stomachs during physical activity.  The Academy of Nutrition and Dietetics suggests using the Harris- Benedict equation (2).  For men the equation is 66.47 + 13.75(weight in kg) + 5(height in cm) – 6.76(age in years) (4).  The Academy states that an activity factor of 1.8 to 2.3 would need to be multiplied to that according to the amount and intensity of physical activity the athlete is partaking in (2).  Overall the athlete needs to experiment with the amount they are comfortable eating and when, to determine when they preform and feel their best.

It is not only the amount of energy they are consuming, but from which macronutrients that energy is coming from, plays a huge influence on how their bodies will perform.  Carbohydrates are essential for all people to consume, as it is our bodies preferred form of energy.  But as athletes push their bodies to extremes, it is even more important that they have enough carbohydrates stored as muscle glycogen, to prevent their bodies from turning to protein to use as an energy source (3).  The Academy recommends a total of 55-65% of calories to come from carbohydrates (2).

Fat is the nutrient that is used for energy during very low intensity exercise and is essential for the absorption and function of fat-soluble vitamins.  It is recommended to have a fat intake of 20- 35% of an athletes total calories.  Roughly 10% should come from saturated fat, 10% from polyunsaturated and 10% from monounsaturated fat sources (2).

Protein is very important to athletes.  It is responsible for building and repairing muscles, it aids in fluid balance and promotes immune function.  Although it is not the preferred energy source during exercise, there are times the body also relies on protein for fuel during sport (5).  Quality protein sources include whey protein, dairy, fresh fish, lean red meats, poultry, pork, eggs, peanut butter and nuts (6).  As mentioned before the amount of protein an athlete needs is still controversial but it is recommend 1.2- 1.7g/kg a day for power athletes and 1.2-1.4g/kg a day for endurance athletes (2).

Although it is very important to intake these nutrients, research on nutrient timing has shown how consuming these nutrients before, during and after exercise has a positive impact on performance as well as recovery.  For example, before working out the athlete should consume smaller meals low in fiber and fat to ensure gastric emptying is achieved before they start their training (2).  Carbohydrates are the preferred energy source during more intense exercise, such as when a person is working at 65-85% capacity (3).  A prework out meal or snack should provide adequate carbohydrates to increase stores in the body that can be used during exercise (2).  Carbohydrates are stored as muscle glycogen in the body and as these supplies run low, the body can become fatigued and the athlete will no longer be able to preform at their best (3).  The Academy states that meals consumed 3-4 hours prior to exercise that included 200-300 grams of carbohydrate showed to enhance performance (2).  However, if eating closer to the time of training this would be too much to consume.  Closer to training 15- 25grams of carbohydrate consumption would be more appropriate (5).

Nutrient consumption during exercise is another consideration.  Previously mentioned was the importance of hydration, electrolytes and carbohydrates.  The Academy suggests the carbohydrate consumption during exercise to be about 30 to 60 grams per hour of activity to ensure the maintenance of blood glucose (2).

Post exercise nutrition is critical to aid the body in recovery and avoid injury.  Carbohydrates are needed to replace glycogen stores (3).  Hydration and electrolytes are needed to replace fluids lost through sweat.  Protein is also critical at this point in providing essential amino acids for the building and repair of muscle tissues (2).  It is commonly stated that 15-20 minutes post exercise; one should consume a 3:1 ratio of carbohydrates to protein for optimal repair and recovery (7).  The Academy suggested consuming a carbohydrate source of glucose or sucrose as compared to fructose as fructose may not be as effective for glycogen synthesis.  They also recommend a carbohydrate intake of 1.0- 1.5g/kg body weight during the first 30 minutes after exercise and then every 2 hours for 4 to 6 hours (2).   At 3 to 4 hours after exercise a regular well-balanced meal should be eaten (7).

As shown from this paper, there are many influences the diet plays on the ability to preform at the athletes best and be able to recover to start training again.  In the end the athlete needs to make sure they are consuming what helps them most, and this is commonly found through trial and error during the off season training.  This paper offers some very good information and suggestions on how athletes can begin to see what helps them enhance their performance best.

REFRENCES

  1. Hydrate Right. The Academy of Nutrition and Dietetics. January 2013.
  2. Position of the American Dietetic Association, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and Athletic Performance. Journal of the Academy of Nutrition and Dietetics. 2009.
  3. Williams M, Anderson D, Rawson E. Nutrition for Health, Fitness & Sport. New York, NY: McGraw Hill; 2013.
  4. Nutrition Care Manual Calculators: Nutrition Care Manual website. http://www.nutritioncaremanual.org/calculators.cfm?ncm_category_id=10&ncm_heading=Updated 2014.  Access December 29, 2014.
  5. Eat Right for Endurance. The Academy of Nutrition and Dietetics. January 2013.
  6. Caspero A. Protein and the Athlete- How Much Do You Need? The Academy of Nutrition and Dietetics. December 2014.
  7. Mohr C. Timing Your Nutrition. The Academy of Nutrition and Dietetics. December 2014.
  8. Denny S. Supplements and Ergogenic Aids for Athletes. The Academy of Nutrition and Dietetics. November 2014.

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