# Hamstring Strength and Architectural Properties Are Associated with Running Biomechanics

## TL;DR

This study explores how hamstring strength and muscle structure relate to running mechanics and injury risk.

## Contribution

The study identifies a complex relationship between running biomechanics and modifiable hamstring injury risk factors.

## Key findings

- Relative eccentric hamstring strength significantly relates to modifiable HSI risk factors.
- BFLH fascicle length is significantly associated with HSI risk factors.
- Running mechanics and muscle properties show a complex interrelationship.

## Abstract

Applied muscular strain and hamstring strain capacity have a joint interaction on hamstring strain injury (HSI) with modifiable risk factors frequently assessed. However, to date there is limited observations on the interaction between these factors. The purpose of the present study was to observe if spatiotemporal characteristics, running kinematics and muscle activation were related to modifiable risk factors of HSI. Twenty-two competitive team sport athletes (24.7 ± 4.3 years, 1.82 ± 0.07 m, 84.9 ± 8.5 kg) participated whereby the Bicep femoris long head (BFLH) fascicle length assessed via ultrasound and isokinetic eccentric hamstring strength was assessed. With running assessment performed at 18 km/h, capturing running kinematics and muscle activation. Multiple linear regressions were used to examine the relationship of running kinematics and muscle activation on the modifiable risk factors of HSI on. The overall model (F2,19) was statistically significant for both relative eccentric hamstring strength (F = 23.58, p < 0.001) and BFLH fascicle length (F = 18.87, p < 0.001) highlighting spatiotemporal characteristics, running kinematics and hamstring activation were found to be significantly related to the modifiable risk factors. There is a complex interrelationship between running mechanics and hamstring muscle properties, with the potential of either cause or consequence association.