Abstract Body (Do not enter title and authors here): Introduction: The impact of exercise on the adult heart has been well studied and associated with better cardiovascular health. However, the exercise-induced physiological adaptations of the youth athlete's heart are not well understood.

Research Questions/Hypothesis: Cardiac screening data will differ significantly based on which sport a youth athlete plays.

Goals/Aims: To assess the impacts of different sports on youth athletes' cardiovascular health.

Methods: The HeartBytes National Youth Database produced by Simon’s Heart was used for this study. The database contains demographics, exercise-related symptoms, ECG data obtained during Simon’s Heart PPEs, and data on various types of sports that athletes participate in. To investigate the effects of each specific sport, we excluded those playing multiple sports from the data set, and employed a propensity score match method to control the confounding influences of race, sex, and exercise intensity. This study used an odds ratio statistic and p-value of 5% criterion to evaluate associations between specific sports and cardiovascular risk factors.

Results: Of the 7425 athletes in the HeartBytes database, the majority were male (60.6%) and White (83.1%). The mean BMI was 21.4 with SD 4.6. The median age was 15.0 years old with an interquartile range 13.5-16.5. There were 279, 120, 179, 552 athletes playing basketball, baseball, football, and soccer only respectively.

Athletes playing basketball had higher odds of exertional symptoms of feeling easily tired (p=0.017), ECG abnormalities (p=0.032), and T wave inversion (p=0.017), but lower odds of ADHD (p=0.03).

Athletes playing baseball had higher odds of asthma (p=0.02) and T wave inversion (p=0.046) if exercising less than 5 hours/week, and higher odds of murmurs (p=0.023) and exertional syncope (p=0.04) if exercising more than 10 hours/week.

Athletes playing football had higher odds of obesity (p<0.0001), hypercholesterolemia (p=0.048), and diabetes (p=0.037) if exercising more than 10 hours/week.

Athletes playing soccer had higher odds of voltage ECG left and right ventricle hypertrophy respectively (p<0.01), but lower odds of obesity (p<0.001).

Conclusion: All sports showed significant impact on youth athletes' health. Further studies are required to understand the physiological adaptations of youth athlete heart.