Influence of the Supplementary Ki-hap Technique and Verbal Encouragement on Abdominal Muscle Activation during Crunch Exercise in Healthy Subjects: A Pilot Randomized Controlled Trial

크런치 운동 시 부수적인 기합 기법과 청각적 격려 적용이 정상인의 복부 근육 활성도에 미치는 영향 : 무작위 대조 예비 연구

Kim, Hyung-Kun;Kim, Chang-Yong;Kang, Jeong-Hyeon;Kim, Hyeong-Dong

  • Received : 2016.02.19
  • Accepted : 2016.03.14
  • Published : 2016.05.31


PURPOSE: The purpose of this study was to investigate the effects of a supplementary Ki-hap technique and verbal encouragement on the activation of abdominal muscles during performance of crunch exercise in healthy subjects. METHODS: 93 subjects were randomly allocated to three group, crunch exercise group (CG), crunch exercise with Ki-hap group (CKG), and crunch exercise with Ki-hap and verbal encouragement group (CKVG), with 31 subjects in each group, respectively. The interventions were conducted over three trials in each group, and measurements were performed on each subject by one examiner in three trials. The activation of rectus abdominis (RA), external oblique (EO), and internal oblique (IO) muscles were evaluated using electromyography (EMG) during performance of crunch exercise with non-Ki-hap, Ki-hap and Ki-hap combined with verbal encouragement. RESULTS: Our results showed a significantly greater increase in the EMG patterns of all muscles during performance of crunch exercise in the CKG (p<0.05) compared to the CG and CKVG. The results also showed that there were significantly greater increase in the activation of EO and IO muscles in those of the CKVG (p<0.05) compared with the CG. CONCLUSION: These findings demonstrated that addition of the Ki-hap technique and verbal encouragement during performance of crunch exercise, at the same time, would suggest positive evidence for improving activation of abdominal muscles.


Abdominal muscle;Crunch exercise;Electromyography;Ki-hap;Verbal encouragement


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