PURPOSE: The purpose of this study was to analyze the activity of brain waves depending on the different type of stretching exercise as a warm-up for Taekwondo competitions in order to find out the feasibility of using EMS during PNF-stretching method. We would like to see the difference between the stretching techniques used by Taekwondo athletes and the stretching methods using EMS. METHODS: A total of three method of treatments were conducted to 8 elite Taekwondo athletes(Age: 25.87±0.99, Height: 185.75±11.01, Weight: 80.87±21.56) repeatedly in random order: PNF Stretching with electric stimulation(EMS+PNF), warm-up exercise with electric stimulation, and PNF stretching without electric stimulation. The EMS+PNF group's electrical treatment was 60 Hz, with five seconds of stimulation and five seconds of rest alternately. Exercise intensity is RPE 15-16 levels. The brain wave condition of all subjects were presented in comparison before and after(post-hoc) treatment procedures. We performed Two-way Repeated Anova test at the difference of the data between the before and after the program. RESULTS: First, EMS part (M = 66.73, SD = 7.23), PNF part (M = 38.02, SD = 7.23), EMS during PNF stretching part (M = 59.33, SD = 7.23) were confirmed in Alpha value. So significant differences were found between warm-up exercise with EMS during PNF-stretching(p<.01); EMS during PNF-stretching and PNF-stretching(p<.05) in Alpha value. In addition, it showed significant increases in alpha value corresponding to duration of treatments(F=4.851, p=.009). Second, significant differences between before and after were found in beta values(F=5.024, p=.026). Third, significant differences were found between EMS (M=151.99, SD=14.93) and PNF-stretching(M=84.67, SD=14.93) in theta value(p<.01). EMS showed higher value than PNF-stretching in theta wave. CONCLUSIONS: This study was showed changes of an alpha wave, which reflects positive emotions, depending on presence of EMS. Thus, it can be considered as more effective method when applying EMS to conventional stretching which leads athletes to feel more effectively treated. The result of the increase in the beta wave was predicted about the difference between EMS stimulation and general stretching by reflecting the characteristics of the beta wave that is activated as cognitive processing occurs. Theta wave is activated when the influence and anxiety of a quiet environment are felt. We are guessed Player thinks that the effect of stretching is low and that the result is reflected when the traditional stretching is performed. Throughout this study, athletes can be expected to show better performance by using EMS during stretching exercise.
experimental schematic diagram
pre-test EEG ↓
EMS EMS+PNF Stretching PNF Stretching
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10 min rest (Between measurements)
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post-test EEG