The Effects of Proprioceptive Neuromuscular Facilitation and Static Stretching Performed at Various Intensities on Hamstring Flexibility

다양한 강도에서 수행된 고유감각신경근육촉진 스트레칭과 정적 스트레칭이 뒤넙다리근의 유연성에 미치는 효과

  • Lim, Woo-taek (Department of Physical Therapy, College of Health and Welfare, Woosong University)
  • 임우택 (우송대학교 보건복지대학 물리치료학과)
  • Received : 2019.09.16
  • Accepted : 2019.11.26
  • Published : 2020.02.20


Background: To prevent or reduce the risk of strain injury, various approaches, including stretching techniques are currently being used. The effect of proprioceptive neuromuscular facilitation (PNF) and static stretching on flexibility has been demonstrated; however, it is not clear which one is superior. Objects: This study aimed to evaluate the differences between the effects of PNF and static stretching performed at various intensities on muscle flexibility. Methods: The maximum voluntary isometric contraction (MVIC) of the hamstrings using the PNF stretching technique was performed in the P100 group, while 70% of the MVIC was performed in the P70 group. The MVIC value obtained during the PNF stretching in both groups was used as a reference for setting the intensity of static stretching. Static stretching was performed at 130% (S130), 100% (S100), and 70% of the MVIC (S70). The active knee extension (AKE) values, defined as the knee flexion angle were measured before stretching (baseline), immediately after stretching (post), and at 3 minutes, 6 minutes, and 15 minutes. Results: PNF stretching produce a greater improvement in flexibility compared with static stretching. Specifically, the ΔAKE was significantly higher in the S100 and S70 groups than in the P100 group at Post. In the comparison of ΔAKE over time in each group, the ΔAKE at Post showed a significant decrease compared to the value at Baseline in the S130 group; however, no significant difference was observed at 6 minutes while a significant increase was noted at 15 minutes. Conclusion: This study found that PNF stretching is more effective than static stretching with respect to increasing and maintaining the flexibility of muscles. In addition, the increase in flexibility at maximal intensity was similar to that observed at submaximal intensity during both PNF and static stretching.



The research was supported by 2019 Woosong University Academic Research Funding.


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