Many other modifiable risk factors have been reported by different authors, with variable levels of evidence and often conflicting, including athlete weight, quadriceps peak torgue, quadriceps flexibility, hip flexor flexibility, ankle dorsi-flexion lunge range of motion, lower limb joint position sense, playing position and hamstring to hamstring ratio. Of these modifiable risk factors, the quadriceps peak torque has shown as strong association with the future incidence of RHI. In reality, it is difficult to evaluate quadriceps peak torque in soccer environment because: I) it does not reflect the position where the hamstring injury is most vulnerable to strain in running and II) most soccer clubs do not have access to isokinetic testing equipment
