LAUSR

BACKGROUND: The delayed blood pressure recovery (BPR) at post-exercise has been in association with a major risk of cardiovascular disease and death. OBJECTIVE: The study focused on evaluating the systolic and diastolic blood pressure recovery (SBPR, DBPR) and the autonomic modulation following treadmill exercise in healthy young adults. Although considerable literature had been published about BPR and HRV, the association between BPR and ultra-short-term HRV has not yet been completely described. METHODS: Fifteen subjects performed exercise with three different intensities on a treadmill, the speed was 6 km/h, 9 km/h, 12 km/h, respectively. SBP and DBP was measured per 30 s in each trial. The synchronous 5-min electrocardiogram (ECG) signals were recorded and HRV30s parameters including SDNN30s, RMSSD30s, SDNN30s/RMSSD30s, SD130s, SD230s and SD130s/SD230s were calculated every 30 s periods in 5 min ECG signals to match the corresponding BPR. RESULTS: The intraclass correlation coefficient (ICC) values and the Bland-Altman plots indicated good consistency and repeatability between HRV30s and HRV5min at three post-exercise trials, with most ICC values > 0.75. Besides, SBPR and DBPR generally decreased and returned to the Rest level in 5 mins. The Spearman correlation coefficients showed strong relationships between BPR and HRV30s sympathetic-vagal balance parameters, i.e., ratio SDNN/RMSSD and ratio SD1/SD2. CONCLUSIONS: These observations represented a new insight into the cardiovascular regulation at post-exercise, which could contribute to physical exercise areas in the future.