Caffeine consumption causes diverse physiologic effects that can affect athletes both positively and negatively. There is a lack of research investigating the long-term effects of caffeine intake on exercise and on overall cardiovascular health in young athletes.
Certain characteristics such as age, body mass index (BMI), race, and medical diagnoses are associated with increased caffeine use, and there is a relationship between caffeine consumption and symptoms during exercise and cardiovascular abnormalities in young athletes.
Level of evidence:
This study utilized the HeartBytes National Youth Cardiac Registry to collect data related to demographics, caffeine use, and physical examination and electrocardiogram (ECG) findings of 7425 12- to 20-year-olds (60.6% male, 39.4% female) who attended a Simon's Heart cardiac screening event between 2014 and 2021. Univariable and multivariable logistic regression models were used for analysis.
Persons who consumed caffeine were more likely to have attention deficit hyperactivity disorder (ADHD) (adjusted odds ratio [aOR], 1.43; CI, 1.15-1.76]; P < 0.01) and more likely to have a BMI ≥30 kg/m2 (aOR, 1.69; CI, 1.27-2.25]; P < 0.01) compared with nondrinkers. After controlling for age, gender, race, and BMI, there were no significant differences in symptoms during exercise (aOR, 1.27; CI, 0.97-1.66; P = 0.08) or abnormal ECG findings (OR, 0.93; CI, 0.66-1.31; P = 0.70) between those who consume caffeine and those who do not.
Caffeine consumption was associated with increased BMI and increased likelihood of having ADHD; however, caffeine use overall was not associated with increased risk of symptoms during exercise or ECG abnormalities.
Whereas caffeine consumption overall did not increase risk of exercise-related symptoms, soda drinkers were at higher risk for symptoms during exercise, and coffee drinkers were at higher risk of syncope with exercise. Prospective studies with longitudinal follow-up and more specific outcomes data is the next step in qualifying the impact of caffeine on young athletes.