Background: While studies have identified the negative cardiovascular effects of obesity, the effects of obesity on youth athletes are less studied. This study investigates the associations between obesity in youth athletes and exercise activity and exertional cardiac symptoms. Methods: The HeartBytes National Youth Database produced by Simon's Heart, a nonprofit that organizes adolescents' sports pre-participation examinations (PPEs), was used. This database contains demographic data, exercise-related symptoms, and electrocardiogram data obtained during PPEs. BMI was converted to percentiles, with obesity defined as BMI ≥95th percentile. Outcomes were evaluated using a chi-squared test with odds ratios (ORs) and 95% confidence intervals (CIs). Results: Of 7363 patients, there were 634 individuals with obesity. Youth athletes within normal weight ranges (5th-85th percentile) had higher exercise rates than those with underweight, overweight, or obesity (p < 0.001 for each). Athletes with obesity had higher odds of exertional symptoms overall (OR: 1.63 [CI: 1.36-1.96]; p < 0.001). However, for athletes who exercised >10 hours a week, there was no association between obesity and exertional symptoms. Athletes with obesity had higher odds of elevated blood pressure (OR: 5.35 [CI: 2.00-14.30]; p < 0.001) and hypercholesterolemia (OR: 3.84 [CI: 2.51-5.86]; p < 0.001). Conclusions: In this dataset, obesity in youth athletes is associated with decreased physical activity and increased exertional symptoms in general. Obesity is not associated with exertional symptoms in athletes who participated in higher weekly physical activity. Further studies are needed to elucidate the cause-effect relationship of these findings.
Keywords: BMI; cardiology; physical activity.