IJCS | Volume 31, Nº5, September / October 2018

508 Figure 2 - Maximal treadmill exercise test in control (C), infarcted sedentary (S), continuous exercise (CE) and accumulated exercise (AE) groups. Values expressed as mean ± SEM. #p < 0.05 vs. Baseline; ¥p < 0.05 vs. Final; *p < 0.05 vs. C; †p < 0.05 vs. S. Feriani et al. Accumulated exercise in infarcted old rats Int J Cardiovasc Sci. 2018;31(5)505-512 Original Article (CE: +100%; AE: +71%). No further differences were observed among exercised groups. At post MI moment, CE group, but not AE, showed reduced physical capacity in comparison with the final assessment (after the last session of ET) (-35%). Nevertheless, MTET values of both trained groups were still higher (100%) in relation with the S group (100%) (Figure 2). Regarding the morphological parameters, body weight was similar among all groups in the beginning of the protocol (~475g). However, after MI, AE group demonstrated significant reduction on body weight in relation to the initial assessment (Figure 3). On the other hand, organ analysis demonstrated increased LV relative weight inAE. There were no further significant differences between the groups in relation to RV, soleus and gastrocnemius relative weight (Table 1). Figure 4 shows the results of lungwater content, an index of pulmonary congestion, in all groups. Data demonstrated a slight, but significant, increase in pulmonary congestion in CE in relation to all the other groups. Discussion The main findings of the present study are that aerobic training, regardless of the arrangement of the program - continuously or fractioned -, causes significant increase on physical capacity of elderly rats, as well as acts protecting against further impairments caused by MI injuries. However, an interesting phenomenon was observed after MI, since CE showed decreased exercise capacity in comparison with the time before MI, as well an elevated index of pulmonary congestion. On the other hand, both parameters were still stable in the AE group, which might indicate a superior protective effect of this kind of intervention in relation to the continuous ET program. Regarding the physical capacity before MI, the data of the present study are in line with most evidence in the literature from animal 17,18 and human studies, 12,19,20 since both trained groups showed increased aerobic capacity after ET (CE: +55%; AE: +33%). However, data have demonstrated inconsistent results regarding the magnitude of the increase after the protocols, so that is possible to observe evidence indicating more favorable results towards continuous protocols, 17,19 whereas others showed highest levels of physical capacity after accumulated aerobic training. 20 In the current study, accumulated and continuous aerobic training propitiated similar improvement on physical capacity. The inconsistencies among these findings could be a