Athletes are commonly screened to identify risk before participation in sports, In the US, they are reevaluated every 2 years (if high school age) or every 4 years (if college age or older). In Europe, screening is repeated every 2 years regardless of age.
Cardiovascular screening
Screening for all children and adults should include a thorough cardiovascular history, with questions about
Known hypertension or heart murmur
Exercise-induced or unexplained syncope Syncope Syncope is a sudden, brief loss of consciousness with loss of postural tone followed by spontaneous revival. The patient is motionless and limp and usually has cool extremities, a weak pulse... read more (including convulsive syncope), near-syncope, chest pain, dyspnea, or palpitations Palpitations Palpitations are the perception of cardiac activity. They are often described as a fluttering, racing, or skipping sensation. They are common; some patients find them unpleasant and alarming... read more
Family history of sudden cardiac death at age < 50 years, arrhythmias Overview of Arrhythmias The normal heart beats in a regular, coordinated way because electrical impulses generated and spread by myocytes with unique electrical properties trigger a sequence of organized myocardial... read more
, dilated Dilated Cardiomyopathy Dilated cardiomyopathy is myocardial dysfunction causing heart failure in which ventricular dilation and systolic dysfunction predominate. Symptoms include dyspnea, fatigue, and peripheral edema... read more 
or hypertrophic cardiomyopathy Hypertrophic Cardiomyopathy Hypertrophic cardiomyopathy is a congenital or acquired disorder characterized by marked ventricular hypertrophy with diastolic dysfunction (eg, due to valvular aortic stenosis, coarctation... read more 
, long QT syndrome Torsades de Pointes Ventricular Tachycardia Torsades de pointes ventricular tachycardia is a specific form of polymorphic ventricular tachycardia in patients with a long QT interval. It is characterized by rapid, irregular QRS complexes... read more , or Marfan syndrome Marfan Syndrome Marfan syndrome consists of connective tissue anomalies resulting in ocular, skeletal, and cardiovascular abnormalities (eg, dilation of ascending aorta, which can lead to aortic dissection)... read more 
Physical examination should routinely include blood pressure in both arms, supine and standing cardiac auscultation, and inspection for features of Marfan syndrome Symptoms and Signs Marfan syndrome consists of connective tissue anomalies resulting in ocular, skeletal, and cardiovascular abnormalities (eg, dilation of ascending aorta, which can lead to aortic dissection)... read more . These measures aim to identify adults as well as apparently healthy young people at high risk of life-threatening cardiac events (eg, people with arrhythmias, hypertrophic cardiomyopathy, or other structural heart disorders).
Testing is directed at clinically suspected disorders (eg, exercise stress testing for coronary artery disease Overview of Coronary Artery Disease Coronary artery disease (CAD) involves impairment of blood flow through the coronary arteries, most commonly by atheromas. Clinical presentations include silent ischemia, angina pectoris, acute... read more 
, echocardiography for structural heart disease, electrocardiogram [ECG] for arrhythmia or long QT syndrome). Routine stress testing in the absence of symptoms, signs, or risk factors is not recommended. European guidelines differ from American guidelines in that a screening ECG is recommended for all children, adolescents, and college-age athletes.
(See also Athlete's Heart Athlete’s Heart Athlete’s heart is a constellation of structural and functional changes that occur in the heart of people who train for prolonged durations (eg,> 1 hour most days) and/or frequently at high... read more and Sudden Cardiac Death in Athletes Sudden Cardiac Death in Athletes An estimated 1 to 3/100,000 apparently healthy young athletes die suddenly during exercise. Males are affected up to 10 times more often than females. Basketball and football players in the... read more .)
Other screening measures
Noncardiovascular risk factors are more common than cardiovascular risk factors. Adults are asked about the following:
Previous or current musculoskeletal injuries (including easily triggered dislocations)
Arthritic disorders, particularly those involving major weight-bearing joints (eg, hips, knees, ankles)
Concussions
Asthma
Symptoms suggesting systemic infection
Heat-related illness
Easy bruising or bleeding
Seizure
Two populations at risk for injuries are commonly overlooked:
Boys who physically mature late are assumed to be at greater risk of injury in contact sports if competing against larger and stronger children.
Overweight or obese people are at increased risk of musculoskeletal problems because of excess body weight and associated forces on the joints and tissues. One risk is overuse injury and soft-tissue inflammation, particularly if people increase intensity and duration of exercise too rapidly. A long-term risk is osteoarthritis Osteoarthritis (OA) Osteoarthritis is a chronic arthropathy characterized by disruption and potential loss of joint cartilage along with other joint changes, including bone hypertrophy (osteophyte formation). Symptoms... read more
affecting weight-bearing joints. Another risk may be injury due to sudden stops and starts if they participate in activities that require jumping or high levels of agility.
Adolescents and young adults should be asked about use of illicit and performance-enhancing drugs Anabolic Steroids Anabolic steroids (anabolic-androgenic steroids) are often used to enhance physical performance and promote muscle growth. When used inappropriately, chronically at high doses and without medical... read more . (Visit the U.S. Anti-Doping Agency web site.)
In girls and young women, screening should detect delayed onset of menarche. Girls and young women should be screened for the presence of the female athlete triad (eating disorders Introduction to Eating Disorders Eating disorders involve a persistent disturbance of eating or of behavior related to eating that Alters consumption or absorption of food Significantly impairs physical health and/or psychosocial... read more , amenorrhea Amenorrhea Amenorrhea (the absence of menstruation) can be primary or secondary. Primary amenorrhea is failure of menses to occur by age 15 years in patients with normal growth and secondary sexual characteristics... read more or other menstrual dysfunction Introduction to Menstrual Abnormalities Some common menstrual abnormalities include Amenorrhea Abnormal uterine bleeding (eg, due to ovulatory dysfunction) Dysmenorrhea Premenstrual syndrome read more , and diminished bone mineral density Osteoporosis Osteoporosis is a progressive metabolic bone disease that decreases bone mineral density (bone mass per unit volume), with deterioration of bone structure. Skeletal weakness leads to fractures... read more 
). Two questions are validated screening measures for eating disorders:
Have you ever had an eating disorder?
Are you happy with your weight?
Contraindications
There are almost no absolute contraindications to sports participation.
Exceptions in children include
Hypertrophic cardiomyopathy Hypertrophic Cardiomyopathy Hypertrophic cardiomyopathy is a congenital or acquired disorder characterized by marked ventricular hypertrophy with diastolic dysfunction (eg, due to valvular aortic stenosis, coarctation... read more
, in which increases in heart rate can increase risk of sudden cardiac deathAcute splenic enlargement Splenomegaly Splenomegaly is abnormal enlargement of the spleen. (See also Overview of the Spleen.) Splenomegaly is almost always secondary to other disorders. Causes of splenomegaly are myriad, as are the... read more or recent infectious mononucleosis Infectious Mononucleosis Infectious mononucleosis is caused by Epstein-Barr virus (EBV, human herpesvirus type 4) and is characterized by fatigue, fever, pharyngitis, and lymphadenopathy. Fatigue may persist weeks or... read more
(Epstein-Barr virus infection) because splenic rupture is a riskSymptomatic or persistent fevers Fever in Infants and Children Normal body temperature varies from person to person and throughout the day. Normal body temperature is highest in children who are preschool aged. Several studies have documented that peak... read more , which may decrease exercise tolerance, increase risk of heat-related disorders Overview of Heat Illness Heat illness encompasses a number of disorders ranging in severity from muscle cramps and heat exhaustion to heatstroke (which is a life-threatening emergency). Heat illness, although preventable... read more , and be a sign of serious illness
Possibly significant diarrhea Diarrhea in Children Diarrhea is frequent loose or watery bowel movements that deviate from a child’s normal pattern. Diarrhea may be accompanied by anorexia, vomiting, acute weight loss, abdominal pain, fever,... read more and/or recent significant vomiting Nausea and Vomiting in Infants and Children Nausea is the sensation of impending emesis and is frequently accompanied by autonomic changes, such as increased heart rate and salivation. Nausea and vomiting typically occur in sequence;... read more because dehydration Dehydration in Children Dehydration is significant depletion of body water and, to varying degrees, electrolytes. Symptoms and signs include thirst, lethargy, dry mucosa, decreased urine output, and, as the degree... read more is a risk
Exceptions in adults include
Known aneurysms Subarachnoid Hemorrhage (SAH) Subarachnoid hemorrhage is sudden bleeding into the subarachnoid space. The most common cause of spontaneous bleeding is a ruptured aneurysm. Symptoms include sudden, severe headache, usually... read more
in the brain or large vessels Overview of Aortic Aneurysms Aneurysms are abnormal dilations of arteries caused by weakening of the arterial wall. Common causes include hypertension, atherosclerosis, infection, trauma, and hereditary or acquired connective... read more 
Relative contraindications are more common and lead to recommendations for precautions or for participation in some sports rather than others, for example:
People with a history of frequent and easily triggered dislocations or multiple concussions Sports-Related Concussion Sports activities are a common cause of concussion, a form of mild traumatic brain injury. Symptoms include loss of consciousness, confusion, memory difficulties, and other signs of brain dysfunction... read more should participate in noncollision sports.
Males with a single testis should wear a protective cup for most contact sports.
People at risk of heat intolerance and dehydration (eg, those with diabetes Diabetes Mellitus (DM) Diabetes mellitus is impaired insulin secretion and variable degrees of peripheral insulin resistance leading to hyperglycemia. Early symptoms are related to hyperglycemia and include polydipsia... read more , cystic fibrosis Cystic Fibrosis Cystic fibrosis is an inherited disease of the exocrine glands affecting primarily the gastrointestinal and respiratory systems. It leads to chronic lung disease, exocrine pancreatic insufficiency... read more
, sickle cell disease or trait Sickle Cell Disease Sickle cell disease (a hemoglobinopathy) causes a chronic hemolytic anemia occurring almost exclusively in people with African ancestry. It is caused by homozygous inheritance of genes for hemoglobin... read more 
, or previous heat-related illness) should hydrate frequently during activity.People with suboptimal seizure control should avoid swimming, weight lifting, and, to prevent injury to others, sports such as archery and riflery.
People who have asthma Asthma Asthma is a disease of diffuse airway inflammation caused by a variety of triggering stimuli resulting in partially or completely reversible bronchoconstriction. Symptoms and signs include dyspnea... read more need to monitor their symptoms closely.
