Investigation of acute effects of hamstring muscle stiffness and flexibility on foam roller models of different densities in professional soccer players

Aim: It was aimed to examine the acute effects of the use of Foam Roller models of different densities on hamstring muscle stiffness and flexibility in professional football players. Material and Methods: Hamstring muscle's stiffness were evaluated using the Myoton Pro device, the flexybility of the hamstring muscle were evaluated using with the unilateral sit-reach test on 21 male professional football players who played in Gaziantep Football Club at aged 18-40. Athletes were randomly divided into groups of seven to use soft, medium and hard foam rollers. The athletes applied the method consisting of two sets of one minute on the dominant hamstring muscle. Measurements were made twice, before the application [BA] and after the application [AA]. Results: The muscle stiffness measurement of the football players was determined BA mean of 16.26 N/m and AA mean of 16.17 N/m. Flexibility measurement was determined BA mean of 28.36 cm and AA mean of 31.05 cm. It was found that the mean of pre-test and post-test did not differ statistically for muscle stiffness (p>0.05) according to measurement times, but statistically differed for flexibility (p<0.05). As a result of the two-way ANOVA test; It was determined that there was no statistically significant difference on muscle stiffness and flexibility between foam roller models applied at different intensities (p>0.05). Conclusion:It shows that foam roller application is important for increasing muscle flexibility, but there is no difference between foam roller models applied at different intensities in terms of removing muscle stiffness and increasing flexibility. Keywords: flexibility, foam rolling, hamstring muscle stiffness, myoton, sports