RESUMO
The purpose of this study was to determine whether exercise training mediated cardiac troponin T (cTnT) and whether this was associated with increases in left ventricular mass (LVM). Fifty-four sedentary obese women were randomised to high-intensity interval training (HIIT, repeated 4-min cycling at 90% VÌO2max interspersed with 3-min rest), work-equivalent continuous aerobic training (CAT, continuous cycling at 60% VÌO2max) or a control group (CON). Resting serum cTnT was assessed using a high-sensitivity assay before and after 12 weeks of training. LVM was determined from 2D echocardiography at the same timepoints. Both HIIT and CAT induced a similar elevation (median 3.07 to 3.76 ng.l-1, p<0.05) in resting cTnT compared with pre-training and the CON (3.49 to 3.45 ng.l-1, p>0.05). LVM index in HIIT increased (62.2±7.8 to 73.1±14.1 g.m-2, p<0.05), but not in CAT (66.1±9.7 to 67.6±9.6 g.m-2, p>0.05) and CON (67.9±9.5 to 70.2±9.1 g.m-2, p>0.05). Training-induced changes in resting cTnT did not correlate with changes in LVM index (r=-0.025, p=0.857). These findings suggest that twelve weeks of either HIIT or CAT increased resting cTnT, but the effects were independent of any changes in LVM in sedentary obese women.