Interval and continuous exercise enhances aerobic capacity and hemodynamic function in CHF rats

Abstract

OBJECTIVE: The aim of the present study was to compare the effects of continuous versus interval aerobic exercise training on hemodynamic parameters, cardiac remodeling, and maximal exercise capacity (MEC) in chronic heart failure (CHF) rats. METHOD: Twenty-four male Wistar rats were subjected to myocardial infarction (MI) surgery. Five weeks post MI, the animals were assigned to one of three groups: sedentary group (CHF-Sed, n=8), aerobic continuous training group (CHF-ACT, n=8), and aerobic interval training group (CHF-AIT, n=8). Treadmill training was performed five times a week for 8 weeks (ACT: 50 min/day at 15 m/min and AIT: 40 min/day with 8 min of warm-up at 10 m/min and exercise at 15 m/min 4×4 min interspersed with 4×4 min at 23 m/min). MEC was evaluated pre and post exercise program. RESULTS: Left ventricular end-diastolic pressure (LVEDP), left ventricular mass/body mass ratio (LVM:BM), and total collagen volume fraction were lower in the trained groups compared with the sedentary group, but no difference was found between the trained groups. Systolic ventricular pressure (SVP) and maximum positive derivative of LV pressure (+dP/dtmax) were higher in the trained groups, but CHF-ACT showed higher +dP/dtmax compared to CHF-AIT. Both training regimens were able to increase MEC. However, the aerobic interval training was superior for improving MEC. CONCLUSION: Aerobic training is an important intervention to improve cardiac function and remodeling and physical capacity in CHF rats. Interval training is a potential strategy to maximize the results, but exercise type and intensity are still topics to be explored.

Chronic heart failure modifies respiratory mechanics in rats: a randomized controlled trial

“…Together, these data characterize the development of marked cardiac dysfunction in the CHF group. In fact, these hemodynamic alterations observed in the present study might induce structural and functional changes, which in turn may impair functional capacity as observed in the literature 27 .…”

Exercise training improves the IL-10/TNF-α cytokine balance in the gastrocnemius of rats with heart failure

“…Besides the anti-inflammatory benefits, regular exercise training seems able to induce hemodynamic adaptations in HF rats. 12 , 16 , 26 , 34 Our results showed a significant reduction in LVEDP, HW/BW and RV/BW after ExT in HF rats, indicating positive effect on cardiopulmonary function. This finding is in line with previous reports showing that low to moderate treadmill running offers beneficial effects on the ventricles of HF rats.…”

FSTL1 as a Potential Mediator of Exercise-Induced Cardioprotection in Post-Myocardial Infarction Rats

“…For instance, twice a week IAE for 12 weeks at the intensity of 4 × 4 minute intervals at 85–95% of peak heart rate can diminish myocardial damage through increasing peak oxygen uptake 23 and improving heart functional capacity and quality of life. LVEDP, left ventricular mass/body mass ratio (LVM:BM) and total CVF were decreased while LVSP and +dP/dt(max) were increased by aerobic interval training (40 min/day with 8 min of warm-up at 10 m/min and exercise at 15 m/min 4 × 4 min interspersed with 4 × 4 min at 23 m/min) in rats with chronic heart failure 53 . These results are consistent with our findings.…”