Age-Related Differences in Hamstring Flexibility in Prepubertal Soccer Players: An Exploratory Cross-Sectional Study

Area of Science:

• Sports Science
• Pediatric Sports Medicine
• Biomechanics

Background:

• Hamstring flexibility is crucial for athletic performance and injury prevention in young athletes.
• Prepubertal soccer players undergo significant physical development, potentially impacting flexibility.
• Limited research exists on the specific changes in hamstring flexibility in prepubertal soccer players across different age groups.

Purpose of the Study:

• To investigate hamstring flexibility trends in prepubertal soccer players aged U8 to U12.
• To determine the influence of chronological age and years of soccer practice on hamstring flexibility.
• To identify age-related differences in hamstring flexibility within this cohort.

Main Methods:

• A cohort of 611 prepubertal Italian soccer players (U8-U12) participated.
• Hamstring flexibility was assessed using the Sit and Reach Test (SAR).
• Statistical analyses included one-way ANOVA, Tukey's post hoc tests, and bivariate/multivariable ordinal regression, with adjustments for Body Mass Index (BMI).

Main Results:

• Significant differences in hamstring flexibility were observed across age groups (F = 32.76, P < 0.0001).
• Older players (e.g., U12) demonstrated significantly less hamstring flexibility compared to younger counterparts (e.g., U8, U9, U10, U11).
• A negative association between age categories and hamstring flexibility was confirmed, even after adjusting for BMI (R² = 0.138, P < 0.0001).

Conclusions:

• Hamstring flexibility declines with increasing age and soccer experience in prepubertal players.
• Older players in this cohort exhibited reduced hamstring flexibility compared to younger players.
• Implementing specific stretching protocols in youth soccer training is recommended to mitigate excessive hamstring tightness and potential injury risks.