Leg joint flexibility and velocity of kicked soccer ball in college age males.

June 29, 2010 / By: Meghan Grathen

The use of stretching prior to athletic performance to reduce injury and enhance athletic performance has been controversial.  A review of the literature concluded that is cannot be recommended to continue or discontinue stretching as there is not sufficient evidence (Gilchrist, Stroup, and Thacker, 2004).  Also, it was suggested that there is a greater ability to increase foot speed when the swinging leg covers more distance (Young, Clothier, Otago, Bruce, and Liddell, 2004).  Thus, the purpose of this research was to examine the importance of stretching and the effects it may have in college age males (age: 20.89±1.45 years; height: 72.56±3.47 inches; weight: 214.42±40.55 pounds).  The hypothesis for this research was that stretching will increase leg joint flexibility and leg joint flexibility will not affect the velocity of a kicked soccer ball.  Research was conducted using nine right leg dominant college age males.  The following leg joint range of motions were measured using a Saunders Digital Inclinometer both with and with out implementing a stretching program on two different days: ankle plantar flexion (31.11±7.20˚ and 25.33±10.61˚), ankle dorsiflexion with knee bent (37.33±11.30˚ and 37.67±7.14˚) and straight (40.67±10.20˚ and 42.11±9.774˚), knee flexion (118.56±7.80˚ and 122.44±6.89˚), hip flexion (124.44±12.00˚ and 126.44±11.58˚), hip extension (23.11±11.35˚ and 25.44±16.79˚), and hip abduction (52.78±10.86˚ and 64.89±9.97˚).  Subjects performed six instep soccer kicks and the velocity of the ball was measured using a Bushnell Radar Gun (40.22±7.34 mph and 41.39±6.20 mph).  Correlation coefficients calculated for leg joint flexibility and velocity revealed A weak negative correlation for knee flexion on day 1 (-0.516) and a strong negative correlation for ankle dorsiflexion with knee bent day 2 (-0.791).  A Pearson Product Moment T-Test performed for stretching and no stretching resulted in a significant p-value for hip abduction (0.026).