Response to letter to the editor

We would like to thank Belkin et al, Nwabuo et al and Dr. Komamura for their comments on our manuscript.¹ The troponins measured were only cardiac troponin I and the reference to troponin T in the abstract is an unfortunate oversight on our part. Table 1 correctly lists troponin I and the reference to troponin T in the discussion refers to data presented from a previous study.² The dichotomous patterns of ventricular hypertrophy, particularly the interaction of concentric or eccentric hypertrophy with sex, were not the primary focus of our study and we were not powered to address these differences. The divergences in modeling pattern may be predictive of future heart failure subtype (e.g. reduced vs preserved ejection fraction) and while our study was not longitudinal in design, we believe concentric remodeling regardless of sex is more likely to be associated with increased hazard for HFpEF on account of increased myocardial stiffening. As the Nwabuo et al point out, longitudinal data to establish this link is lacking. A reliable non-invasive measure of myocardial stiffness that could be broadly applied in a longitudinal cohort study would certainly help to establish this link. We are currently finalizing data analysis of echocardiographic markers in this cohort to understand the interaction of vigorous aerobic exercise training and myocardial stiffness. Lastly, all patients in the study had glomerular filtration rates > 60 mL/min/1.73m².