Effect of acupuncture on heart rate variability during prolonged high-intensity training in soccer players

OBJECTIVE: To investigate the effects of acupuncture therapy compared with sham acupuncture on heart rate variability(HRV) in 24 elite soccer players during 4-week, high-intensity training sessions.METHODS: The subjects were randomly divided into two groups: acupuncture group(AG) and sham acupuncture group(SG). In addition, AG had been implemented two times/week to stimulate Zusanli(ST 36), Hegu(LI 4), Shenshu(BL 23), and Chize(LU5). While SG, had been applied to utilize a special "placebo-needle" technique on the same sites.What's more, the HRV parameters were calculated before and after interventions, respectively.RESULTS: First, stress index(SI) had a significantly increased in SG(P = 0.031) compare pre-test with post-test, however, no significantly difference in AG(P = 0.102). Secondly, standard deviation of N-N intervals(SNDD) have enormously significantly high-er in AG when comparing baseline with post therapy(P = 0.001), while, declined in SG(P = 0.827).Meanwhile, the root mean square of successive differences(RMSSD) were significant differences in AG(P = 0.023). What's more, when the high-frequency(HF) were significantly higher in AG(P = 0.047) after receiving the acupuncture therapy, the lowe-frequency(LF) power were decreased but no significant in AG and SG. Comparing with pre-experiment, the ratio of LF/HF was lower in AG, but higher in SG. Furthermore, it was significant difference when compare the post-experiment parameters of AG with SG(P = 0.015). And HF parameters have significance(P = 0.005) compare between two groups during the post-experiment.CONCLUSION: Based on evidence, acupuncture therapy on special acupoints could strengthen the parasympathetic nervous activity and modulates the balance between parasympathetic and sympathetic activity in soccer players while they engage in high-intensity training.