The young athlete who desires to compete at higher levels must train longer and harder than athletes of previous generations. Success among young athletes may be defined by invitation to national or international competitions, or by college scholarships. Although only .02% to .5% of high school athletes will go on to participate at a professional level,1 the number of young athletes becoming single-sport specialists continues to rise.
To reach the professional level, today's youth athlete often forgoes other opportunities while training for their sport. Young participants may specialize in a specific sport at an early age, sacrificing multisport participation to allocate time, skill development, and finances toward training year-round with talented peers and coaches in the pursued sport. The accolades that these athletes receive from their parents and coaches deliver a powerful message to train above and beyond their fellow competitors. The increased dedication to intense training regimens presents physical, emotional, and cognitive challenges to the young athlete that may put overall health at risk. The pediatric health care provider has the opportunity to educate the athlete and parent on these important issues.
Athletes who follow rigorous training programs often seek to stand out from their peers. For example, in preparation for a 5-km race high school cross country athletes will customarily run 45 to 55 miles per week. The amount of time, energy, and physical demands placed upon the competing youth may lead to diminished rewards and overuse syndrome if wellness is not also maintained. A good example of this concept would be a swimmer who routinely swims 8,000 yards in daily practice to train for a 100-yard sprint but then fails to turn in school assignments, skips breakfast, oversleeps the morning alarm 2 to 3 times per week, and presents to the doctor with fatigue. The pediatric health care provider may best identify, monitor, and treat causes of underperformance by obtaining a thorough sports history, comprehensive physical examination, and laboratory analysis.
The sport-specific history should identify type and position of sports in which the child participates, hours of sports played per week, level of participation (recreational, high school, collegiate, travel team), number of weeks or months of the year participating in a sport, and the recognition of other sport participation throughout the year. Those athletes who abruptly increase their amount of hours of practice, intensify their training regimen (eg, increased volume, “play up” on a more competitive varsity team as a younger athlete), or play an additional sport or on another team at the same time are likely to suffer overuse injuries.
The clinician should also discuss time spent away from sports participation to identify nonsport interests and to take care of the psychologic well-being of the athlete. An athlete who loses interest in school, friends, and hobbies may be showing signs of overtraining syndrome (Table 1). Additional symptoms include fatigue, chronic pain, and elevated heart rate.2 For example, a cross-country runner whose race finish times increase despite continued perseverance in practice, complains of diffuse body pain, or shows a lack of interest in school may be experiencing overtraining syndrome. Deficient scholastic performance or inability to complete tasks may alert parents to signs of overtraining.2
Symptoms of Overtraining Syndrome
The Role of Rest and Sleep
Athletes require sleep to allow for rest and recover from injury. Adolescents routinely do not obtain the 8 to 9 hours of sleep recommended by the National Sleep Foundation.3 Students will often do homework late into the night. Evening practices may disrupt usual dinner times so that the athlete is eating just before going to bed. Access to electronics becomes a constant temptation that may also compromise sleep. These issues can lead to a constant state of sleep deprivation.
Sleep is an important factor that affects sports performance, physical health, emotional well-being, and recovery.2 Progressive sleep loss negatively affects quality of training and increases likelihood of injury.4 To better appreciate the athlete's sleep habits, the physician should discuss customary bedtime and awakening periods, sleep latency or disturbance experienced throughout the night, napping habits, and location of sleep. Discussing bedtime routines allows the pediatrician to identify problems and discuss the importance of abstaining from electronics 30 minutes prior to bed and removing devices (television, laptop, tablet, computer, and phone) from the bedroom. It is helpful to implement a bedtime routine of dimming the lights, avoiding unnecessary noise, and engaging in a calming activity (reading, drawing, meditation) to ready the mind for sleep. The physician may also endorse sleeping in the same location each night to allow the body to activate sleep more easily. The bed should be reserved for sleep, and a different location should be sought to study, read, or use electronics.
Rest or downtime also improves sports performance so that the athlete may recover from the physical demands of practice and competition, rehabilitate injury, and attend to school or social opportunities.2 Athletes who participate in multiple sport appearances in a single day (tournament schedule, football and swimming two-a-days, multiple sports) should schedule adequate rest periods to allow for recovery between bouts. The American Academy of Pediatrics Council on Sports Medicine and Fitness (AAP COSMF)5 recommends limiting sports participation to 5 days per week and scheduling at least 1 day of rest from all physical activity per week. It is important to schedule time off from sports, including weekly nonpractice days and even months off to allow the body to rest and prevent burnout and overtraining. The AAP COSMF also advises that the athlete participate in a different physical activity (cross-train) for 2 to 3 months per year to heal previous injuries and reduce the likelihood of future injury.5 Lack of adequate rest may increase the risk for burnout.2
Parents and athletes are oftentimes unaware of appropriate food choices, diet composition, and timing of food consumption that best support training needs. Marketing campaigns target the desire to improve performance by sponsoring famous athletes who then entice consumers to choose specific foods or supplements. The consumer can be persuaded to purchase dietary supplements over proper food items without realizing the potential harm these items may cause.
As a result of the 1994 Dietary Supplemental Health and Education Act, supplements do not need to be approved by the US Food and Drug Administration (FDA), and manufacturer claims do not require proof before labels are placed on packages.6 Many nutritional supplements are contaminated with other products that may cause harm to the growing body. The consumer assumes a significant risk when ingesting dietary supplements.6 Athletes may inadvertently consume contaminants that are banned by the regulating bodies of sports organizations. Identification of performance-enhancing substances through positive drug-screening tests is grounds for immediate disqualification in most organizations. The physician may serve as a clarifying source of information by dispelling myths, identifying false advertising, and educating the athlete on proper foods choices.
Proper nutrition is critical for athletic performance, and the developing athlete must consume adequate calories to support nutritional needs for growth.7 Young athletes must follow a high-calorie, well-balanced diet to support the energy demands of sports participation. Optimal performance necessitates the athlete to consider quantity, quality, and timing of food consumed. Proper timing of food ingestion allows accessibility of nutrients and energy while performing, and eating during the recovery period acutely replaces those expenditures (Table 2). The American College of Sports Medicine and the American Dietetic Association recommend a diet balanced in macronutrients (carbohydrates, protein and fats) to support sport performance and decrease the risk of illness.8
Suggested Food Choices to Support Training
Carbohydrates allow quick access to energy during high-intensity periods of activity, such as sprinting or weight lifting. Carbohydrates prevent hypoglycemia by replenishing liver and glycogen stores that are exhausted during exercise. The daily amount of carbohydrate consumption, carbohydrate loading prior to activity, and replacement after the activity for an adolescent can be found in Table 3.8 Recovery carbohydrates should be consumed immediately after and again 2 hours after exercise. Whole grains, wheat breads, unrefined pasta, and whole fruits and vegetables are high-quality carbohydrates that provide macronutrients to support athletic training.
Recommended Dietary Allowance for the Adolescent Athlete
Protein intake may easily be achieved through the consumption of meat, poultry, fish, eggs, and nuts. Athletes do not need to rely upon protein supplements to meet the daily and exercise requirements that support optimal sports performance. The growing adolescent should consume .8 g of protein per kilogram of body weight to support daily metabolic needs.8 The endurance athlete should increase daily requirement to 1.2 to 1.4 g of protein per kilogram of body weight, and the anaerobic athlete or power trainer should increase consumption to 1.6 to 1.7 g of protein per kilogram of body weight (Table 3).8
Fats serve as a transporter for essential amino acids and carrier of fat-soluble vitamins for daily physiologic function. Fats also serve as an energy source during low-intensity endurance activity through release from storage via triglycerides in the muscle. Twenty percent to 35% of total daily caloric intake should consist of fat to sustain daily activity.8 Decreasing percentage fat below the recommended amount may cause athletic performance to suffer.
To properly advise the athlete on the importance of a balanced diet, a detailed history of typical meals and snacks eaten or skipped throughout the day should be obtained. The athlete's energy reserves are best identified through a food diary that records type and amount of food consumed and notes the time in relation to practice or competition. This tool may then teach the athlete to focus on timing of food consumption in relation to exercise. Once educated, athletes may plan appropriate meals and snacks to eat before, during, and after sports activity to properly prepare for caloric expenditure and replace energy stores. Consultation with a registered dietician who is sports trained may be helpful for the young athlete. A list of sports trained and registered dietitians can be found at the Sports, Cardiovascular, and Wellness nutrition website.9
The athlete who desires weight loss should also discuss how weight reduction and target weights will be obtained at specific time intervals. Reducing weight too quickly or unsafely (through use of diuretics, laxatives, and emetics) can cause an energy-deficient state and increase risk for dehydration and heat injury. If not executed properly and with the guidance of a health professional and registered dietician, the process of obtaining a smaller body size/weight may be detrimental to athletic performance and increase likelihood of injury.
It is also important to discuss hydration with the young athlete. Dehydration negatively affects the body's ability to regulate basal temperature, increases risk for heat illness, and impairs athletic performance. Dehydration in excess of 3% to 5% percent may lead to reduced strength and endurance performance, reduced plasma and blood volume, compromised cardiac output (elevated heart rate, smaller stroke volume), and impaired thermoregulation, glomerulofiltration, and liver glycogen stores. Athletes should avoid consumption of alcohol, caffeine, and nicotine as these substances may also increase risk for dehydration through diuresis, vasodilatation, and vasoconstriction.
Athletes should be encouraged to drink before, during, and after sports participation for proper hydration. Drinking two or more 8-ounce cups of water 1 hour before exercise and one 4-ounce cup of water 10 minutes prior to activity assures proper hydration. As exercise continues, 8 ounces of water should be consumed for every 20 minutes of activity. When exercise exceeds 90 minutes, the athlete may consume a carbohydrate beverage or sports drink to properly replace electrolytes lost during exercise and to increase water retention. After the sporting activity, the athlete should drink 16 to 24 ounces of water for every pound of weight lost or until they void a large amount of clear urine. All fluid replacement should occur within 2 hours after exercise to properly rehydrate. It has been demonstrated that athletes will consume more fluids if they are flavored and served cold.9 Consultation with a registered dietician who is sports trained may be helpful for the young athlete.10 (A list of sports trained and registered dietitians can be found at the Sports, Cardiovascular, and Wellness nutrition website.9)
Other causes for fatigue, disinterest, and poor performance may include use of illicit substances and ergogenic drugs. These substances alter mood, enhance athletic performance, or are used for recreational purposes. The National Collegiate Athletic Association, American Medical Association, and American College of Sports Medicine do not condone the use of nontherapeutic drugs by student-athletes. Examples of such substances include, but are not limited to, alcohol, amphetamines, ephedrine, ma huang (ephedra), anabolic-androgenic steroids, barbiturates, caffeine, cocaine, heroin, lysergic acid diethylamide, phencyclidine, marijuana, and all forms of tobacco. The use of many of these substances may be identified through drug-screening tests. Athletes who test positive for banned substances may be subjected to immediate disqualification from the regulating sporting body.
Laboratory evaluation for hormonal and nutritional deficiencies may be needed in the endurance athlete, menstruating female athlete, female athlete with menstrual dysfunction, or in those who limit caloric intake or avoid specific food groups. These people may be at increased risk for micronutrient deficiencies, iron-deficiency anemia, and poor bone mineral density. Laboratory testing can help guide recommendations for nutritional and vitamin supplementation (Table 4).
Suggested Laboratory Assessment for the Overtraining Athlete
Intense athletic training by children has been shown to delay sexual maturation, and those athletes who train at the highest levels are at increased risk.11 A history of primary or secondary amenorrhea should be assessed by performing a complete physical examination, pelvic examination (as indicated), and laboratory assessment. A pregnancy test may be warranted. Tests of thyroid-stimulating hormone, prolactin, and follicle-stimulating hormone will assess for pituitary tumors, thyroid dysfunction, polycystic ovarian disease, premature ovarian failure, and chronic illnesses.11 Luteinizing hormone, testosterone, dehydroxyprogesterone sulfate, and 17-hydroxyprogesterone may be indicated if androgen excess (hirsutism or acne) is present or if low estrogen levels are identified.11
Menstruating female athletes who present with a history of secondary amenorrhea often report loss of menses during the most strenuous season of sports participation. Although this is often perceived by teenage female athletes, coaches, and parents to be normal behavior, bone mineral density may suffer as a result of prolonged amenorrhea.11 As estrogen secretion decreases during the endurance or training season, athletes are more likely to develop stress fractures and endure osteopenia and osteoporosis later in life. By counseling young female athletes to decrease their training regimen or increase caloric consumption to support return of regular menses, these risks can be reduced. Calcium and vitamin D supplementation may also be advised. The recommended daily allowance of calcium for adolescents is 1,200 mg, and this should be increased to at least 1,500 mg for amenorrheic athletes.11 One may also consider obtaining a dual-energy X-ray absorpiometry test to assess bone mineral density to guide management in athletes who have had a high risk for stress fractures (such as the femoral neck), multiple stress fractures, or amenorrhea for more than 6 months.
Infectious mononucleosis is another possible cause of chronic fatigue syndrome among adolescents. Athletes involved in high school, collegiate, and Olympic-level competition are at increased risk for infection when traveling and living in close-contact environments. Mononucleosis and the symptoms of Epstein-Barr virus (EBV) can adversely affect athletic performance by producing symptoms of fever, fatigue, and spleen enlargement. Laboratory assessment with heterophile antibody (monospot) may screen for presence of EBV, but the false-negative rate of 25% supports the use of confirmatory laboratory assessment for EBV-specific immunoglobulin G (IgG) and immunoglobulin M (IgM) antibodies. The presence of IgM antibodies indicates an acute infection, and an elevated level of IgG antibodies indicates prior infection, and both are seen within a few weeks of initial infection.
Although splenic rupture is a rare complication of EBV infection, splenomegaly occurs in up to 50% to 100% of athletes due to lymphocytic infiltration, which also causes splenic fragility.12 Splenomegaly may be identified through abdominal palpation on physical examination, but physical examination is unreliable so all athletes with EBV infection should be considered at risk for splenic rupture. The finding of splenomegaly in an athlete who has complaints of fatigue requires a serum heterophile antibody (monospot) test and/or EBV panel to test for infectious mononucleosis. Once symptoms of fever, fatigue, and muscle soreness have resolved and a minimum of 3 weeks since onset of symptoms has passed, the athlete may slowly return to light, noncontact activity.13 All athletes who have splenomegaly should be withheld from contact sports for a minimum of 28 days from the onset of symptoms to reduce risk for splenic rupture.13 Any identified hepatic or splenic enlargement must be resolved before any sport training can be resumed.
Clinical judgment is essential when evaluating an athlete who presents with fatigue. The signs and symptoms of overtraining may be similar to those presented by poor sleep, inadequate diet, or infectious mononucleosis. The clinician should screen for symptoms of disinterest, depression, and poor school and sport performance in addition to obtaining a thorough sport and diet history. Laboratory assessment will assist in the evaluation of the physiologic cause of fatigue. It is important to discuss the athlete's goals, desires, and personal motivations in confidence to support continued psychologic development. Youth sport participation should support lifelong physical activity, enjoyment, and healthy competition. The pediatric health care provider can serve as an educator to promote healthy participation and provide guidance.
- National Collegiate Athletic Association. Estimated probability of competing in athletics beyond the high school interscholastic level. www.ncaa.org/sites/default/files/Probability-of-going-pro-methodology_Update20123_0.pdf. Accessed February 10, 2016.
- Meeusen R, Duclos M, Foster C, et al. Prevention, diagnosis, and treatment of the overtraining syndrome: joint consensus statement of the European College of Sport Science and the American College of Sports Medicine. Med Sci Sports Exerc. 2013;45(1):186–205. doi:10.1249/MSS.0b013e318279a10a [CrossRef]
- Eaton DK, McKight-Eily LR, Lowry R, et al. Prevalence of insufficient, borderline, and optimal hours of sleep among high school students-United States, 2007. J Adolesc Health. 2010;46:399–401. doi:10.1016/j.jadohealth.2009.10.011 [CrossRef]
- Milewski MD, Skaggs DL, Bishop GA, et al. Chronic lack of sleep is associated with increased sports injuries in adolscent athletes. J Pediatr Orthop. 2014;34(2):129–133. doi:10.1097/BPO.0000000000000151 [CrossRef]
- Brenner JSAmerican Academy of Pediatrics Council on Sports Medicine and Fitness. Overuse injuries, overtraining and burnout in child and adolescent athletes. Pediatrics. 2007;119(6):1242–1245. doi:10.1542/peds.2007-0887 [CrossRef]
- Calfee R, Fadale P. Popular erogogenic drugs and supplements in young athletes. Pediatrics. 2006;117:e577–e589. doi:10.1542/peds.2005-1429 [CrossRef]
- Intensive training and sports specialization in young athletes. American Academy of Pediatrics. Committee on Sports Medicine and Fitness. Pediatrics. 2000;106:154–157.
- Hoch AZ, Goosen K, Kretschmer T. Nutritional requirements of the child and teenage athlete. Phys Med Rehabil Clin N Am. 2008;19(2):373–398. doi:10.1016/j.pmr.2007.12.001 [CrossRef]
- Sports Cardiovascular, and Wellness Nutrition. http://www.scandpg.org. Accessed February 11, 2016.
- Meyer F, Bar-Or O, Salsberg A. Hypohydration during exercise in children: effect on thirst, drink preference, and hydration. Int J Sport Nutr. 1994;4:22–35.
- American Academy of PediatricsCommittee on Sports Medicine and Fitness. Medical concerns in the female athlete. Pediatrics. 2000;106:610–613. doi:10.1542/peds.106.3.610 [CrossRef]
- McCorkle R, Thomas B, Suffaletto H, Dietrich J. Normative spleen size in tall healthy athletes: implications for safe return to contact sports after infectious mononucleosis. Clin J Sport Med. 2010;20(6):413–415. doi:10.1097/JSM.0b013e3181f35fe5 [CrossRef]
- Auwarter PG. Infectious mononucleosis: return to play. Clin Sports Med. 2004;23:485–497. doi:10.1016/j.csm.2004.02.005 [CrossRef]
Symptoms of Overtraining Syndrome
Decline in physical performance despite training
Psychologic disturbance: mood changes, depression, agitation, restlessness, anxiety
Apathy: loss of interest in school, friendships, and family and inability to complete daily tasks
Deficient scholastic performance: trouble concentrating, academic decline
Sleep disturbance: insomnia
Lack of appetite
Loss of body weight
Suggested Food Choices to Support Training
|3–4 hours before training
||Small balanced meal: protein and carbohydrates, low in fiber
||Turkey and cheese sandwich with fruit
Bean or chicken soup and yogurt
Pasta with tomato meat sauce
Peanut butter and bagel, fruit and yogurt
Smoothie with granola
Oatmeal with almonds and fruit
Skim milk and banana
Cottage cheese, crackers, and grapes
Small lean turkey/beef burger and salad
|2 hours before training
||Bagel with light cream cheese
Banana and yogurt
Small fruit/vegetable and crackers
||Immediate carbohydrate snack
||Sports drink and protein bar
Low-fat chocolate milk
Yogurt smoothie and fruit
Graham crackers and peanut butter
|1–2 hours postactivity
||Meal balanced with protein and carbohydrates
||Turkey, whole wheat pita, and vegetable
Chicken, brown rice, and milk
Beans and rice with cheese and vegetable
Stir fry with chicken, fish, or pork
|Snack throughout day
||Light and on the go
||Trail mixes: dried fruits, nuts, and seeds
Fresh fruit or sliced vegetables
Recommended Dietary Allowance for the Adolescent Athlete
||Fat (% total kcal)
|Preparation 1–2 hours before
|Replacement/recovery after endurance training
|Replacement/recovery after anaerobic training
Suggested Laboratory Assessment for the Overtraining Athlete
||Female Athlete with Amenorrhea
||Repeat/High-Risk Stress Fractures
||PES/Drug Test (with consideration)
|CBC and differential
Iron panel (TIBC % saturation)
Vitamin D 25-OH
||Urine pregnancy test