relationships to be discussed, directly or indirectly, referred to or illustrated with or without recognition within the presentation.

5/19/2016 1 Common Medical Issues in Endurance Sports Naomi L. Albertson, M.D. Family Medicine/Sports Medicine 2 I, Naomi Albertson, M.D., nor my family member(s), have any relevant financial relationships to be discussed, directly or indirectly, referred to or illustrated with or without recognition within the presentation. 3 Objectives: understand, diagnose and prevent/treat the condition GI distress ( Runner s Gut ) in endurance athletes Cardiac dysfunction in endurance athletes Hyponatremia in endurance athletes 4 History of Endurance Running Aborigenes, San, and Kalahari tribes: Long distance running as a method for hunting. The hunter would run at a steady pace for 3 hours to several days, not allowing the prey to cool down. Eventually the prey would collapse from exhaustion and heat illness. 5 History of Endurance Running As cultures developed, long-distance running became more important as a form of tradition or ceremony and as a means of relaying messages. (Hopi and Tarahumara) 6 Ancient Greece was famous for its running messengers. One of the most famous running messengers is Philippides, who according to the legend ran from Marathon to Athens to announce the Greek victory over the Persians in the Battle of Marathon in 490 B.C. He collapsed and died as he delivered the message we won 7 Modern Day Endurance running The history of cross country running is linked with the game of hare and hounds, where a group of runners would cover long distances to chase a leading runner. The Crick Run in England in 1838 was the first recorded instance of an organized cross country competition. 8 Data from ultrarunning magazine 2013 shows More than 1200 ultramarathon events and almost 70,000 participants 9 10 11 12 Marathon des Sables The world's toughest footrace- approximately 150 miles of Moroccan desert while carrying 1

10 5/19/2016 11 12 Marathon des Sables The world's toughest footrace- approximately 150 miles of Moroccan desert while carrying their food and supplies on their backs. The race is broken into several stages with time limits for each one. Organizers have scattered mandatory checkpoints with water along the way to ensure runners stay hydrated. 13 Badwater Ultra The Badwater Ultramarathon is a 135-mile, summer race from Death Valley (280 feet below sea level) to the trailhead of Mount Whitney (almost 8,300 feet above sea level). Temperatures reach around 130 degrees Fahrenheit, while asphalt bakes to nearly 200, hot enough to force runners to race on the road's white lines or risk their shoes melting. Every 15 minutes, support crews douse the racers with ice water to prevent overheating. 14 What could possibly go wrong? GI distress ( Runner s Gut ) Cardiac dysfunction Hyponatremia 15 Runner s Gut Search runners gut on Google and find 471,000 results Definition of GI distress : stomach pain, nausea, vomiting and/or diarrhea associated with athletics. Mechanisms have been debated to be either due to microtrauma vs. ischemia. 16 Who gets runner s gut? 1 37-60% runners get GI distress in 50-100 mile races (Dr. Kristin Stuempfle, PhD) 2 For those who race >100 miles GI distress is the #1 reason for dropping out and for those who finish the #1 issue that impacted performance 17 18 Physiology? Mechanical? Nutrition? 19 Decreased GI blood flow causes 1) GI motility slow down 2) Absorption changes 3) Permeability changes 20 Changes in Esophageal motility 1 Esophageal motility slows LES relaxes 21 2 HEARTBURN/ REFLUX 2

20 1 5/19/2016 2 HEARTBURN/ REFLUX 21 Changes in Stomach motility Moderate to high intensity exercise DECREASES stomach motility Dehydration DECREASES stomach motility Both cause bloating, cramps, nausea and vomiting 22 Decreased GI blood flow causes 1) GI motility slow down 2) Absorption changes 3) Permeability changes 23 Absorption changes Exercise less than 2 hours does not change the absorption of CHO and water Exercise > 2 hours may decrease absorption High intensity exercise may also decrease the absorption of CHO and water 24 Decreased GI blood flow causes 1) GI motility slow down 2) Absorption changes 3) Permeability changes 25 Permeability changes? High intensity exercise may cause increased permeability of the GI tract and allow bacterial translocation (? GI symptoms) 26 Physical impact of jostling? 27 Nutrition and Nausea 28 Nutrition? What about fat? Does it help or hinder in GI issues in endurance races? 29 Dr. Stuempfle studied 15 runners at the Javelina Jundred 161 km race 10 males, 5 females Extensive dietary information recorded Symptoms of GI distress recorded 30 Higher fat percent may help? 31 More CHO s, not statistically significant 32 Higher rate of fat intake decreases GI distress 33 More protein, not statistically significant 34 35 36 3

31 5/19/2016 32 33 More protein, not statistically significant 34 Faster rate of fluid intake decreases GI distress 35 Summary 36 In summary To avoid GI distress in endurance runners consider: 1) higher intake of fat 2) faster intake of fat (more often) 3) maintain hydration 37 Cardiac Dysfunction He collapsed and died as he delivered the message we won Why did he die? 38 Left heart pumps oxygenated blood to the exercising muscles. Blood is returned via the venous system to the lungs, oxygenated and moved to the left heart to feed the exercising muscles. As exertion increases, heart rate increases and stroke volume increases to increase the cardiac output. 39 Normal cardiac adaptation to exercise (wikipedia definition) Athletic heart syndrome is a non-pathologic condition in which the human heart is enlarged (cardiomyopathy) and the resting heart rate is lower than normal. These changes are thought to be due to an increased stroke volume and primarily affect the RIGHT Ventricle and Right atrium (CO = SV x HR) Athletic heart syndrome is common in athletes who routinely exercise more than an hour a day, and occurs primarily in endurance athletes. 40 Sudden Cardiac Death (SCD) Marathoners: 1 event per 100,000 participants Causes of SCD: Athletes younger than 30 = genetic causes such as hypertrophic cardiomyopathy, anomalous coronary arteries, dilated cardiomyopathy, and congenital long QT syndrome. Athletes older than 30 years, CHD and acute myocardial infarction and ischemia are the predominant causes of exercise-related SCD 41 How much exercise is too much? Cardiac dysfunction and elevated blood markers of myocardial injury have been reported after prolonged strenuous exercise. Some research suggests that in athletes who compete in repetitive distance events that they may have an increased risk of cardiac scarring and irreversibility of their RV size IS THERE CAUSE FOR CONCERN??? 42 43 4

5/19/2016 IS THERE CAUSE FOR CONCERN??? 42 Wen C.P., Wai J.P., Tsai M.K. Minimum amount of physical activity for reduced mortality and extended life expectancy: a prospective cohort study. Lancet. 2011;378(9798):1244 1253. 43 Trivax J.E., Franklin B.A., Goldstein J.A. Acute cardiac effects of marathon running. J Appl Physiol. 2010;108(5):1148 1153 cardiac troponin, creatine kinase MB, and B-type natriuretic peptide, have been documented to increase in up to 50% of participants during and after marathon running the significance of the elevated cardiac biomarkers after endurance efforts remains uncertain may be entirely benign 44 Trivax J.E., Franklin B.A., Goldstein J.A. Acute cardiac effects of marathon running. J Appl Physiol. 2010;108(5):1148 1153 NO morphological changes to the left atrium or ventricle or evidence of ischemic injury to any chamber. There were no significant arrhythmias. Conclusions: Marathon running causes dilation of the right atrium and right ventricle, reduction of right ventricular ejection fraction, and release of cardiac troponin I and B-type natriuretic peptide but does not appear to result in ischemic injury to any chamber. 45 So keep running??? 46 2012 European Heart Journal Andre La Gerche et al 1 Examined whether myocardial dysfunction following intense endurance exercise affects the RV more than the left ventricle (LV) and whether cumulative exposure to endurance competition influences cardiac remodeling (including fibrosis) in well-trained athletes. Forty athletes were studied at baseline, immediately following an endurance race (3 11 h duration) and 1-week postrace 2 Conclusions: Intense endurance exercise causes acute dysfunction of the RV, but not the LV. Although short-term recovery appears complete, chronic structural changes and reduced RV function are evident in some of the most practiced athletes 47 some individuals may develop chronic dilatation of the RV and RA with patchy myocardial scarring in response to the recurrent volume overload and excessive cardiac strain. These abnormalities are often asymptomatic and probably accrue over many years But they may predispose to serious arrhythmias such as atrial fibrillation and/or ventricular arrhythmias (VAs). 48 What does it all mean? Endurance running is NOT cardioprotective, may have increased all cause mortality and may predispose some individuals to SCD and arrhythmias. 5

5/19/2016 48 Endurance running is NOT cardioprotective, may have increased all cause mortality and may predispose some individuals to SCD and arrhythmias. Further investigation is warranted to identify the exercise threshold for potential toxicity, screening for at-risk individuals, and ideal exercise regimens for optimizing CV health. For now CV benefits of vigorous aerobic ET appear to accrue in a dose-dependent fashion up to 1 hour daily, beyond which further exertion produces diminishing returns and may even cause adverse CV effects in some individuals. 49 So what happened? SCD? Arrhythmia? 50 EAH: Exercise Associated Hyponatremia 51 Terminology Hyponatremia: Below-normal plasma sodium level, as determined by a blood test Symptomatic hyponatremia: Below-normal plasma sodium level with outwardly visible related signs and/or symptoms such as nausea, lethargy, confusion, seizure or altered mental status Hypernatremia: Above-normal plasma sodium level, as determined by a blood test 52 Exercise-associated hyponatremia (EAH) first was described in Durban, South Africa, in 1981; subsequently, Noakes et al. (3) in 1985 described the occurrence of severe hyponatremia in four athletes who participated in endurance events that were longer than 7 h. 53 How many are affected? One of the most common reasons for a runner to seek medical attention and is an important cause of race-related fatalities 2002 Boston Marathon study, Almond et al. found an incidence of 13 percent of all 488 finishers were hyponatremic. 54 Speedy et al. (21) investigated 330 athletes who finished an ultramarathon race. In his study, 58 (18%) were hyponatremic (defined as a serum sodium <135 mmol/l) 55 Who gets EAH? 56 Water Balance 1 Amount of water consumed in food and drink equals the amount of water excreted. Regulated by behavioral mechanisms, including thirst and salt cravings. 2 6

55 56 1 5/19/2016 Regulated by behavioral mechanisms, including thirst and salt cravings. Kidneys are critical and adjust the concentration of urine to either maintain or rid the body of excess water 2 Vasopressin (ADH), a peptide hormone secreted by the hypothalamus allows water reabsorption via the collecting ducts. Without ADH, little water is reabsorbed in the collecting ducts and dilute urine is excreted. 57 Sodium Balance 1 aldosterone, a hormone produced by the adrenal cortex causes sodium reabsorption. Aldosterone secretion is controlled two ways: 2 1) The adrenal cortex directly senses plasma osmolarity. When the osmolarity increases above normal (more concentrated), aldosterone secretion is inhibited. The lack of aldosterone causes less sodium to be reabsorbed in the distal tubule. 2) The kidneys sense low blood pressure (which results in lower filtration rates and lower flow through the tubule). This triggers renin-producing cells which then produces angiotensin II. Angiotensin II stimulates the adrenal cortex to produce aldosterone and sodium is reabsorbed 58 Hyponatremia in Endurance Runners 1 Theory: If you eat excessive sodium you can pull more water into the intravascular volume which would allow improved performance and prevent dehydration and EAH. (many supplements have high sodium or preloading sodium to achieve hyperhydration) 2 Reality: If you take in excessive sodium you do retain water (ADH is inhibited) and increase weight with increased risk of hyponatremia 59 Research from Dr. Martin Hoffman, WSER The more sodium you intake, the more you weigh by the end of the race. So there is a suggestion that sodium helps prevent weight loss. The runners with the highest amount of salt tab supplementation took an equivalent of 72 S Caps!!! (314 mg sodium per cap) 60 1 Runners of 100-mile races are expected to lose between 4 and 5% of their body weight. Most runners with symptomatic hyponatremia tend to have gained weight while racing. (documented by Dr. Hoffman at WSER and Dr. Noakes). 61 Do ultra athletes need to take in extra salt? 1 NO 2 Sodium supplementation during an ultra actually has no significant effect on the blood level of sodium at the end of the race (Winger 2013). Runners who only drink to thirst and do not take supplemental sodium also maintain a 62 7

61 5/19/2016 1 2 level of sodium at the end of the race (Winger 2013). Runners who only drink to thirst and do not take supplemental sodium also maintain a normal (expected) body weight during a 100-mile run. 62 Recommendations for athletes The first is to drink only according to thirst and no more than 400 to 800 ml/h. The second recommendation is to use the USA Track and Field guidelines or other methods to estimate hourly sweat losses during exercise and avoid consuming amounts that are greater than this amount during endurance events. This is facilitated by serial measurements of weights during and after exercise with the goal to maintain weight or even finish exercise with a slightly lower weight. That these recommendations can be effective was demonstrated by Speedy et al., who were able to show that prerace education and limiting fluid availability at a race were able to reduce the incidence of hyponatremia without deleterious effects. 63 Treatment of EAH 64 Treatment of EAH 1) Evaluate the athlete: Mental status? Seizure? Fluid status? Euvolemic, hypovolemic, hypervolemic (puffy?) i-stat? 2) If you feel that the athlete is hyponatremic start HYPERTONIC saline, NOT normal saline. IV hydration with NS should be reserved for athletes who manifest clear clinical signs of volume depletion and used cautiously with mandatory monitoring of serum sodium levels. The treatment of severe (serum [Na] <120 mmol/l) or symptomatic EAH requires the administration of hypertonic saline. Current recommendations are to start with 250cc of hypertonic saline and recheck sodium levels. Plan to accompany your athlete to the hospital 65 EAH: In summary Thirsty? Drink. Craving salt? Eat something salty. Feeling bloated? Stop drinking. If they re in your medical tent start Hypertonic saline 250cc wide open. 66 Questions? 67 Sources Acute cardiac effects of marathon running, Justin E. Trivax, et al. Journal of Applied Physiology 2010 Vol. 108 no. 5, 1148-1153 Exercise-induced right ventricular dysfunction and structural remodeling in endurance athletes Andre La Gerche, European Heart Journal (2012) 33, 998 1006 Maron B.J., Pelliccia A., Spirito P. Cardiac disease in young trained athletes: insights into 8

5/19/2016 athletes Andre La Gerche, European Heart Journal (2012) 33, 998 1006 Maron B.J., Pelliccia A., Spirito P. Cardiac disease in young trained athletes: insights into methods for distinguishing athlete's heart from structural heart disease, with particular emphasis on hypertrophic cardiomyopathy. Circulation. 1995;91(5):1596 1601. Pluim B.M., Zwinderman A.H., van der Laarse A., van der Wall E.E. The athlete's heart: a meta-analysis of cardiac structure and function. Circulation. 2000;101(3):336 344. Maron B.J., Pelliccia A. The heart of trained athletes: cardiac remodeling and the risks of sports, including sudden death. Circulation. 2006;114(15):1633 1644. Pelliccia A., Culasso F., Di Paolo F.M., Maron B.J. Physiologic left ventricular cavity dilatation in elite athletes. Ann Intern Med. 1999;130(1):23 31. Pelliccia A., Maron B.J., Di Paolo F.M. Prevalence and clinical significance of left atrial remodeling in competitive athletes. J Am Coll Cardiol. 2005;46(4):690 696. Pelliccia A., Maron B.J., Spataro A., Proschan M.A., Spirito P. The upper limit of physiologic cardiac hypertrophy in highly trained elite athletes. N Engl J Med.1991;324(5):295 301. Noakes Hoffman,M Exercise associated hyponatremia and hydration status in 161-km ultra marathons, Med Sci Sports Ex, 213;45: 784-91 9