Normalized Eccentric Hamstring Strength in Collegiate American Football: Position-Based Norms and Longitudinal...

Area of Science:

• Sports Science
• Biomechanics
• Strength and Conditioning

Background:

• Eccentric hamstring strength is crucial for athletic performance and injury prevention in American football.
• Understanding position-specific strength differences can inform targeted training programs.

Purpose of the Study:

• Establish normative values for normalized eccentric hamstring strength in collegiate American football players.
• Evaluate differences in normalized strength based on player position, age, and team affiliation.
• Assess longitudinal changes in normalized eccentric hamstring strength across competitive seasons.

Main Methods:

• Measured eccentric hamstring strength in 332 NCAA Division I athletes using the NordBord device.
• Normalized strength to body mass (N·kg-1).
• Employed multiple linear regression and repeated measures ANOVA for data analysis.

Main Results:

• Skill, power, and special teams athletes demonstrated significantly greater normalized strength than linemen.
• Age and team affiliation were significant predictors of normalized strength.
• Longitudinal analysis revealed no significant changes in normalized strength over three seasons.

Conclusions:

• Normalized eccentric hamstring strength norms vary meaningfully by player position and team program.
• Position-specific strength benchmarks are valuable for guiding individualized training, rehabilitation, and return-to-play strategies.
• No significant strength changes were observed over time in this experienced athlete cohort.