The Hemodynamic Response of the Vertebral Artery to 3 Time Durations of the Static Stretching Exercise in the End Position of Contralateral Cervical Rotation

Objectives: To evaluate the effect of 3 different time durations of sustained end-range cervical rotation during static stretching exercises on the hemodynamics of the vertebral artery. Methods: This observational study used Doppler ultrasonography to measure the average vertebral artery hemodynamics at the sustained end-range cervical rotation after 3 time durations of static stretching exercise: 10 seconds, 30 seconds, and 60 seconds. The sustained end-range cervical rotation was applied to 30 asymptomatic male participants. Results: The peak systolic velocity 35.2 ± 6.9 cm/s and the end systolic velocity 12.7 ± 1.6 cm/s reduced significantly, while resistive index 0.74 ± 0.03 increased after 60 seconds of sustained end-range contralateral cervical rotation by 39.1%, 32.4%, and 8.8%, respectively, compared with the neutral position. There were no significant differences found between peak systolic velocity and resistive index after a stretching duration of 60 and 30 seconds. Similarly, there were no notable changes in end systolic velocity when comparing 10 seconds with 30 seconds. Conclusion: The static stretching exercise using sustained end-range cervical rotation for 60 seconds induced marked changes in the hemodynamics of the vertebral artery.