(19) CORRELATION BETWEEN JOINT RANGE OF MOTION, BALANCE, AND BALL VELOCITY FROM A SOCCER KICK

Abstract

Determining what affects a soccer balls velocity can help increase a player’s chance of scoring. Identifying which variables make the strongest impact can lead to better training to increase ball velocity for a wide scope of athletes.

Purpose: The current study aimed to investigate the effects range of motion and joint stability had on ball velocity performed by NCAA Division II women’s soccer athletes.

Methods: Four participants, ages 18-22, completed full range of motion and joint stability tests. A handheld goniometer was used to measure range of motion (ROM) at the hip, knee, ankle, and trunk. Measurements were taken on both the right and the left side of the body in order of hip flexion, extension, internal then external rotation, knee flexion, ankle dorsiflexion, plantarflexion, inversion, eversion, and trunk rotation. Each joint measurement was taken three times and the average was used for analysis. The Y-balance test was used for testing joint stability and balance. Leg length was measured and used to standardize the reach distance of each leg. Participants and were given six practice trials in three directions with each foot: anterior reach, posteromedial reach, posterolateral reach. Participants performed three test trials in each direction and had a one-minute break between trials. Max reach distance was recorded where the most distal part of the foot reached in half centimeters. For analysis of ball velocity and rotational velocity for the instep soccer kick, 3D motion camera Cortex 8.1 and corresponding force plate were used with Helen-Hayes marker locations. The markers were placed on the right and left sides of the body starting at the center of the forehead, side of the head, shoulder at the acromion process, upper arm between the acromion and olecranon, medial and lateral epicondyles of the elbow, the forearm laterally between the olecranon and radial styloid, the wrist at the ulnar and radial styloid, the back on the spine between the shoulders, the back at the sacrum, the pelvis under the last rib, the ASIS, the thigh midway between the patella and ASIS, the knee at the lateral and medial condyle, midway between the medial malleolus and the patella, the ankle at the medial and lateral malleolus, the heel above the calcaneus, and the foot at the proximal 2^nd metatarsal. A marker was placed on the ball with silver tape to help with holding. Ball velocity was determined by peak speed. Mean values from each direction on each limb were used for data analysis. Data analysis was done using the bivariate correlations with 0.95 confidence intervals and were computed using SPSS Statistics version 28 for the resultant ranges.

Results: Significant correlations were found between ball velocity and right hip flexion (-0.966), left hip flexion (-0.890), right hip external rotation (-0.811), and left ankle plantarflexion (-0.877).

Conclusion: No positive correlation between range of motion or joint stability and ball velocity was observed. The significant correlations found were all negative, this may be because the recorded values measured were peak range of motion and composite Y-balance, but the subject doesn’t reach peak range of motion during a kick. PRACTICAL APPLICATION: These data findings suggest athletes and coaches can identify the primary action in their sport and improve function to increase velocity.


Acknowledgements: None