Long-term clinical consequences of intense, uninterrupted endurance training in olympic athletes.
Level 4 - case-series / case-control
Uncontrolled longitudinal cohort study evaluating cardiac outcomes over time in a single elite athlete cohort
PubMed 20378081 · doi:10.1016/j.jacc.2009.10.068
What was done
Echocardiographic dimensions, ventricular function, and clinical outcomes were longitudinally evaluated in 114 Olympic endurance athletes (78% male; mean age 22 ± 4 years) free of cardiovascular disease at baseline. Athletes trained and competed across 2 to 5 consecutive Olympic Games (344 total Olympic events) over a follow-up period ranging from 4 to 17 years (mean 8.6 ± 3 years).
What was found
Zero cardiac events and zero new cardiomyopathy diagnoses occurred during follow-up. Left ventricular (LV) ejection fraction remained stable (62 ± 5% to 63 ± 5%; p = NS) with no regional wall motion abnormalities. LV volume (142 ± 26 ml vs. 144 ± 25 ml; p = 0.52) and LV mass index (109 ± 21 g/m² vs. 110 ± 22 g/m²; p = 0.74) showed no significant changes, and LV filling patterns remained normal. Left atrial dimension exhibited a slight increase from 37.8 ± 3.7 mm to 38.9 ± 3.2 mm (p < 0.001).
Why it matters
The study provides long-term reassurance that prolonged, extreme endurance conditioning does not lead to progressive left ventricular systolic or diastolic impairment or overt cardiomyopathies in elite athletes.
Limits
The cohort represents a highly selected survivor population of elite Olympic athletes, which may introduce selection bias against individuals susceptible to exercise-induced maladaptation. The study lacked a non-athletic sedentary or moderate-exercise control group. Female athletes were underrepresented (22%), and advanced imaging modalities like cardiac magnetic resonance or continuous arrhythmia monitoring were not reported in the abstract.
Cited by
- supports Antonio Pelliccia's studies of multi-time Olympians showed that heart size does not progressively enlarge over 12 to 16 years of sustained high-intensity Olympic training and competition.