Effects of Rugby Training Exposure on Knee-Jerk Reflex Magnitude: A Feasibility Study.

Area of Science:

• Neuromuscular Physiology
• Sports Science
• Biomechanical Analysis

Background:

• The patellar reflex is a fundamental neuromuscular response.
• Quantifying reflex changes due to athletic training is crucial for understanding adaptation and injury risk.
• Existing methods for reflex quantification can be complex or inaccessible.

Purpose of the Study:

• To develop and validate a novel, accessible method for quantifying the patellar reflex.
• To investigate the influence of rugby training level on reflex magnitude, asymmetry, and sensitivity.
• To explore potential training-induced neuromuscular adaptations.

Main Methods:

• Utilized a novel force transducer and ankle-mounted accelerometer to measure lower-limb angular velocity.
• Assessed 64 male participants across four groups: control, amateur, semi-professional, and professional rugby players.
• Employed repeated-measures ANOVA and distributional analyses to evaluate reflex characteristics over 20 trials per leg.

Main Results:

• Demonstrated a significant, progressive decrease in patellar reflex magnitude with increasing rugby training intensity (p<0.0001).
• Found no significant difference in reflex asymmetry between dominant and non-dominant legs (p=0.411).
• Observed significantly lower reflex sensitivity in professional players compared to controls (p<0.0001).

Conclusions:

• The developed method offers an accessible and accurate approach to patellar reflex quantification with potential clinical applications.
• Increased rugby training leads to a progressive diminution in patellar reflex responses, suggesting training-dependent neuromuscular plasticity.
• Understanding these reflex adaptations can inform injury prevention strategies for athletes and aid clinical assessments.