Kinematics analyses related to stretch-shortening cycle during soccer instep kicking after different acute stretching

• Published in: Journal of strength and conditioning research Vol. 26; no. 11; p. 3010
• Main Authors: Amiri-Khorasani, Mohammadtaghi, Mohammadkazemi, Reza, Sarafrazi, Soodeh, Riyahi-Malayeri, Shahin, Sotoodeh, Vahid
• Format: Journal Article
• Language: English
• Published: United States 01.11.2012
• Subjects: Adolescent; Adult; Biomechanical Phenomena; Humans; Knee Joint - physiology; Male; Muscle Contraction; Muscle Stretching Exercises - methods; Muscle, Skeletal - physiology; Plyometric Exercise; Soccer - physiology; Time Factors; Young Adult
• ISSN: 1064-8011; 1533-4287
• DOI: 10.1519/JSC.0b013e3182443442

The purpose of this study was to examine the effects of static and dynamic stretching within a preexercise warm-up on angular velocity of knee joint, deepest knee flexion (DKF), and duration of eccentric and concentric contractions, which are relative to the stretch-shortening cycle (SSC) during instep kicking in professional soccer players. The kicking motions of dominant legs were captured from 18 Olympic professional male soccer players (height: 180.38 ± 7.34 cm; weight: 69.77 ± 9.73 kg; age: 19.22 ± 1.83 years) using 4 digital video cameras at 50 Hz. There was a significant difference in the DKF after the dynamic stretching (-3.22 ± 3.10°) vs. static stretching (-0.18 ± 3.19°) relative to the no-stretching method with p < 0.001. Moreover, there was significant difference in eccentric duration after the dynamic stretching (0.006 ± 0.01 seconds) vs. static stretching (-0.003 ± 0.01 seconds) relative to the no-stretching method with p < 0.015. There was a significant difference in the concentric duration after the dynamic stretching (-0.007 ± 0.01 seconds) vs. static stretching (0.002 ± 0.01 seconds) relative to the no-stretching method with p < 0.001. There was also a significant difference in knee angular velocity after the dynamic stretching (4.08 ± 3.81 rad·s) vs. static stretching (-5.34 ± 4.40 rad·s) relative to the no-stretching method with p < 0.001. We concluded that dynamic stretching during warm-ups, as compared with static stretching, is probably the most effective way as preparation for the kinematics characteristics of soccer instep kick, which are relative to the SSC.