Altered sagittal plane mechanics is associated with Functional Movement Screen deep squat score

Area of Science:

• Sports Medicine
• Biomechanics
• Movement Science

Background:

• The Functional Movement Screen (FMS) is widely used to assess movement quality in athletes.
• The deep squat (DS) is a key component of the FMS, but its individual score validity requires further establishment.
• Understanding the biomechanical basis of FMS scores is crucial for its application in sports settings.

Purpose of the Study:

• To determine the validity of the FMS deep squat (DS) assessment.
• To compare sagittal plane kinematics between participants with different FMS DS observer scores.
• To investigate if kinematic differences correlate with FMS DS scoring in adolescent male cricket bowlers.

Main Methods:

• Seventeen injury-free adolescent male cricket bowlers were assessed using the Optitrack motion capture system.
• Participants performed the deep squat (DS) and were scored by observers using standard FMS criteria.
• Kruskal-Wallis and Mann-Whitney U tests were used to compare joint angles between scoring groups (low, altered, perfect).

Main Results:

• Significant differences were found in femur-to-horizontal angle between high and low scoring groups (p=0.04, r=0.61) and altered and low scoring groups (p=0.03, r=0.66).
• Significant differences were also observed in torso verticality between high and low scoring groups (p=0.02, r=0.66) and altered and low scoring groups (p=0.02, r=0.72).
• These kinematic variations indicate objective differences in movement execution corresponding to subjective FMS DS scores.

Conclusions:

• The study demonstrates that kinematic differences exist among participants who receive different observer scores for the FMS deep squat (DS).
• These findings support the validity of the FMS DS in differentiating movement quality based on sagittal plane kinematics.
• Further research is recommended to explore frontal plane kinematics and the concurrent validity of individual FMS scoring criteria.