Differences in Cardiac Parameters among Elite Rowers and Subelite Rowers

UNLABELLED: There is significant individual variability in the cardiac adaptation that occurs in response to exercise training. Factors associated with this variability remain incompletely understood. To date, the relationship between the competition level at which athletes participate and their underlying cardiac parameters has not been explored. PURPOSE: The purpose of this study was to determine whether parameters of cardiac structure and function differ significantly among elite competitive rowers (ER), subelite competitive rowers (SR), and sedentary controls (C). METHODS: Cardiac parameters were assessed in ER (n = 20), SR (n = 20), and C (n = 20) using two-dimensional, tissue Doppler, and speckled-tracking echocardiography. RESULTS: Physiologic cardiac remodeling was present in both ER and SR as evidenced by the significant differences in the majority of structural and functional parameters in both rower groups when compared with C. When compared with SR, ER were found to have greater left ventricular (LV) end-diastolic volume (76 +/- 6 vs 71 +/- 8 mL x m(-2), P = 0.02), LV mass (150 +/- 11 vs 134 +/- 16 g x m(-2), P = 0.002), and right ventricular (RV) end-diastolic chamber dimensions (15.6 +/- 0.9 vs 13.9 +/- 1.5 cm(2) x m(-2), P < 0.001). Further, ER demonstrated significantly more enhancement of RV systolic function (peak strain = 36% +/- 7% vs 31% +/- 6%, P = 0.008) and late diastolic relaxation in both the LV (A' = 4.2 +/- 1.3 vs 3.2 +/- 0.9 cm x s(-1), P = 0.01) and the RV (A' = 6.6 +/- 1.4 vs 4.3 +/- 1.3 cm x s(-1), P < 0.001). CONCLUSIONS: Although cardiac remodeling occurs in both ER and SR, specific aspects of cardiac structure and function differ between rowers who compete at the elite and the subelite levels of sport.