Kinetic and Kinematic Analysis of the Phases of Kicking during Accurate and Maximal Effort Conditions in Female Soccer Players
Soccer is one of the most popular sports in the world and the substantial increase in participation over the last decade adds significance to understanding kicking mechanics as kicking is a key skill during a game. The biomechanics of soccer kicking have been widely investigated and there is a conventional belief that a tradeoff exists between speed and accuracy during kicking performance. However, the kinetics and kinematics of the kicking leg during the approach to the ball remain unclear and whether or not instep soccer kicks can be performed without a speed-accuracy tradeoff. The purpose of this study was to investigate the kinetic and kinematic differences between accurate and maximal effort soccer kicking in female soccer players. Twenty female soccer players from the college club or varsity level performed three trials of an accurate kick and three trials of a maximal effort kick. Bilateral hip, knee and ankle joint angles and velocities and ground reaction forces (GRFs) of the kicking leg (KL) and plant leg (PL) were calculated. In addition, correlation coefficients were calculated between variables in each condition. During maximal effort kicking, players significantly increased peak hip, knee and ankle angles (p = 0.000, p = 0.000, p = 0.034), angular velocities (p = 0.000, p = 0.000, p = 0.004), and foot velocity (p = 0.000) in the KL. This was likely the result of the significant increase in peak horizontal GRF in the KL (p = 0.000) and PL (p = 0.000). Peak horizontal GRF in the KL had the strongest correlation with foot linear velocity in accurate kicking (R = 0.77*) compared to in maximal effort kicking (R = 60*), and had a stronger influence on foot velocity compared to peak horizontal GRF in the PL in both accurate (R = 0.31*) and maximal effort (0.23) conditions. This suggests that peak horizontal GRF in the KL, rather than in the PL, plays a more important role in kick velocity, especially when kicking accurately. Results indicate that increasing horizontal GRF in the KL in both conditions is key to improving velocity since that variable is highly correlated in each condition. In addition, less variation of horizontal GRFs in the KL in maximal effort kicking indicate faster kicks result in more consistent foot velocities and suggests that players reduce variability as they approach maximum velocity. These results provide evidence that accuracy may not have to be sacrificed when kicks are faster if players practice accurate performances when kicking with maximum velocity due to the less variability in the initial programmed pattern of movement during fast performances. Coaches and trainers may utilize these results to develop training protocols that involve increasing GRFs of the KL and practicing kicks that are both accurate and fast to increase overall accuracy during maximum velocity instep soccer kicks.
Reeves, Kelsey. (November 2019). Kinetic and Kinematic Analysis of the Phases of Kicking during Accurate and Maximal Effort Conditions in Female Soccer Players (Master's Thesis, East Carolina University). Retrieved from the Scholarship. (http://hdl.handle.net/10342/7641.)
Reeves, Kelsey. Kinetic and Kinematic Analysis of the Phases of Kicking during Accurate and Maximal Effort Conditions in Female Soccer Players. Master's Thesis. East Carolina University, November 2019. The Scholarship. http://hdl.handle.net/10342/7641. September 19, 2020.
Reeves, Kelsey, “Kinetic and Kinematic Analysis of the Phases of Kicking during Accurate and Maximal Effort Conditions in Female Soccer Players” (Master's Thesis., East Carolina University, November 2019).
Reeves, Kelsey. Kinetic and Kinematic Analysis of the Phases of Kicking during Accurate and Maximal Effort Conditions in Female Soccer Players [Master's Thesis]. Greenville, NC: East Carolina University; November 2019.
East Carolina University