Effect of Lifeguard Activity Time on HRV-Autonomic Nervous System Changes

다국어 초록 (Multilingual Abstract)

Objectives This study was conducted to find out the changes in heart rate and autonomic nervous system according to water lifeguard activity time. Methods In order to achieve the purpose of the study, eight male college students who obtained a lifeguard certificate and had field experience were selected as subjects for the study, and a total of three tests were conducted every hour after the break. SA-2000E was used to derive the research results, and one-way ANOVA analysis was performed with SPSS 20.0 for data processing. Results HR was 80.33±6.33 at rest, 78.23±9.01 at 1 hour of activity, 75.12±8.32 at 2 hours, and 77.68±10.98 at 3 hours. SDNN showed 57.32±14.81 at rest, 52.33±13.87 at 1 hour of activity, 64.46±21.12 at 2 hours, and 55.21±16.92 at 3 hours. TP was found to be 7.88±0.98 at rest, 7.73±0.52 at 1 hour of activity, 8.52±0.53 at 2 hour, and 7.61±0.87 at 3 hours. VLF was 7.02±1.01 at rest, 7.05±0.52 at 1 hour of activity, 8.11±0.76 at 2 hours, and 7.13±0.75 at 3 hours. LF was 6.32±0.87 at rest, 6.07±0.82 at 1 hour of activity, 7.14±0.62 at 2 hour, and 7.03±0.57 at 3 hours. HF was 4.35±1.04 at rest, 3.87±1.28 at 1 hour of activity, 5.67±0.98 at 2 hours, and 5.20±0.96 at 3 hours. LF/HF was 6.34±2.34 at rest, 8.47±4.92 at 1 hour of activity, 7.02±3.31 at 2 hour, and 6.83±3.95 at 3 hours. There were no significant differences in HR, SDNN, LF, and HF, while there were significant differences in TP, VLF, and LF/HF. Conclusions It is analyzed that there will be a positive effect on stress, autonomic nerve control, and concentration after 2 hours of activity. The significantly higher proportion of sympathetic nerves after an hour of activity can be attributed to the tension caused by the start of work, and in these vulnerable times, it is necessary to form a team to develop and apply a program that can increase workers' concentration.