Comparative Analyses of Implementation of Connected Sensors on Heart Rate Variability in Middle School Judo Athletes Versus Non-Athletes

Abstract

Background and aim. This study aimed to investigate the differences in heart rate variability (HRV) between judo athlete and non-athlete middle school students using wearable heart rate sensors. HRV is a key indicator of autonomic nervous system function and cardiovascular health, with higher variability generally associated with better fitness and stress resilience. Methods. Sixty-seven middle school students were recruited and divided into two groups: an experimental group (EG) of judo athletes (n = 39, height 162.4 ± 7.6 cm, weight 52.7 ± 6.3 kg, age 12.8 ± 1.3 years) and a control group (CG) of non-athletes (n = 37, height 159.1 ± 6.9 cm, weight 53.2 ± 7.3 kg, age 13.2 ± 0.8 years). The CG participants did not engage in any competitive sports. HRV metrics, including mean heart rate (mean HR), mean R-R intervals, standard deviation of normal R-R intervals (SDNN), root mean square of successive differences (RMSSD), low-frequency (LF), high-frequency (HF), and LF/HF ratio, were measured using connected sensors. Independent t tests were used to compare HRV parameters between the two groups, with a significance level set at p < 0.05. Results. Results showed that the EG had significantly higher mean R-R intervals (t = 2.245, p < 0.05) and significantly lower mean HR (t = –2.149, p < 0.05) compared to the CG. These findings suggest that judo training enhances parasympathetic activity and reduces resting heart rate, indicating improved cardiovascular efficiency. Additionally, time-domain HRV metrics, such as SDNN and RMSSD, were higher in the EG, reflecting greater autonomic adaptability. Conclusions. Judo training appears to positively influence HRV in middle school students, promoting better cardiovascular health and autonomic regulation. The use of wearable sensors proved effective in monitoring these physiological adaptations, highlighting their potential for real-time health and fitness assessments in young populations.