Assessing isometric kicking force and post-match responses using the Kicker test.

Area of Science:

• Sports Science
• Biomechanics
• Exercise Physiology

Background:

• Monitoring athlete strength is crucial for performance and injury prevention.
• Existing protocols may not adequately capture combined hip flexion and knee extension capacity.
• Assessing recovery post-match is vital for training load management in soccer.

Purpose of the Study:

• To determine the inter-session reliability of a novel isometric strength assessment protocol (the Kicker).
• To evaluate the Kicker's suitability for monitoring soccer players' force capacity over 72 hours post-match.
• To assess the combined hip flexion and knee extension force changes following competitive soccer matches.

Main Methods:

• The Kicker protocol was tested for reliability across three sessions in 20 athletes.
• Isometric force output was measured in 17 male academy soccer players for 72 hours post-match.
• Data analysis included intraclass correlation coefficients (ICC), typical error, and effect sizes.

Main Results:

• The Kicker demonstrated high inter-session reliability (ICC >0.95) for measuring limb force.
• A significant decrease in force output was observed for 72 hours post-match (-5.8% to -12.5%).
• The protocol identified sustained suppression of force capacity in both kicking limbs post-competition.

Conclusions:

• The Kicker assessment provides a reliable measure of combined isometric hip flexor and knee extensor force.
• This protocol serves as a viable tool for monitoring soccer players' recovery and force capacity deficits post-match.
• Sustained force suppression highlights the importance of recovery strategies for 72 hours after competitive play.