Effects of one set moderate strength exercise on cardiovascular parameters

The aim of this study was to investigate the effect of moderate intensity strength exercise (SE) on autonomic balance and spontaneous barorreflex sensitivity (BRS) in rats. We used male Wistar rats (280–320g) that were divided into 2 groups (n=5 for each group): Sham‐(SG) and Trained‐Group (TG). TG rats were subjected to SE (1 set of 10 series with 10 repetitions) in a squat‐training apparatus. SG rats were sham trained. Before SE test, we determined the one‐repetition maximum (1RM), which means the maximum weight lifted by each animal. For this experiment we used sets of 60% of 1RM. The rats were anesthetized (sodium thiopental, 50 mg/kg, i.p.) and the right carotid was instrumented with a catheter for blood pressure (BP) and pulse interval recording. The variability of pulse interval, BP and BRS were analyzed. The SE was able to decrease the mean arterial pressure (MAP) 60 to 90 min (TG = 132 ± 2.7mmHg to 117 ± 1.6mmHg vs SG = 131 ± 2.6mmHg to 129 ± 1.7mmHg) after SE test. SE also reduced LFsys (25% lower) when compared to SG and increased BRS 45 to 90 min after exercise (TG=1.6±0.4mmHg/s to 2.4±0.6 mmHg/s vs SG= 1.9±0.1 mmHg/s to 1±0.07 mmHg/s). SE was able to increase LF/HF ratio (82%) and heart rate (7%). In summary moderate SE was able to reduce MAP despite higher cardiac sympathetic activity observed during all experimental period. Research support: Fapitec‐SE, CNPq, CAPES.