Joint-Specific and Cross-Joint Strength Profiles in Relation to Maximal Soccer Kicking Speed

Area of Science:

• Biomechanics
• Sports Science
• Human Movement

Background:

• Maximal soccer ball kicking speed is crucial for performance.
• Understanding the biomechanical and neuromuscular factors influencing kicking speed is essential for training optimization.
• Previous research has explored various strength and activation parameters, but their direct link to maximal kicking speed requires further clarification.

Purpose of the Study:

• To investigate the relationship between lower-limb mechanical strength, composite strength indices, and neuromuscular activation with maximal soccer ball kicking speed.
• To determine the predictive value of specific strength measures and generalized neuromuscular activation on kicking performance in trained soccer players.

Main Methods:

• A cross-sectional study involving 25 male soccer players.
• Isometric ankle and knee torques measured using an isokinetic dynamometer.
• Neuromuscular activation assessed via surface electromyography (sEMG) during a squat jump.
• Maximal kicking speed measured using Doppler radar.

Main Results:

• Unadjusted analyses showed moderate correlations between some ankle strength variables and composite measures with kicking speed.
• No significant relationships were found for knee strength indices or sEMG variables.
• All initially observed significant correlations lost statistical significance after false discovery rate (FDR) correction.

Conclusions:

• Isolated isometric lower-limb strength and generalized neuromuscular activation assessed during a squat jump have limited independent explanatory power for maximal soccer kicking speed.
• Task-specific strength and activation patterns may be more critical for maximal kicking performance than general measures.