title: Sex-related differences in joint-angle-specific functional hamstring-to-quadriceps strength ratios.
abstract: OBJECTIVE
  To examine and compare sex-related differences in the functioning of the hamstrings and quadriceps muscles and the isokinetic hamstrings eccentric-to-quadriceps concentric functional ratio (H/QFUNC).
  
  
  METHODS
  Fifty male and 46 female young adults completed this study. Each participant carried out an isokinetic assessment to determine isokinetic concentric and eccentric torques during knee extension and flexion actions at 3 different angular velocities (60, 180 and 300°/s) adopting a lying position. The H/QFUNCwas calculated using peak torque (PT) values and 3 different joint-angle-specific torque values (15°, 30° and 45° of knee extension). A repeated measures analysis of variance was used to compare the results, and post hoc analyses using Friedman correction were employed.
  
  
  RESULTS
  There were statistically significant effects of angular velocity, joint angle and sex on the H/QFUNC(p < 0.01). Thus, the H/QFUNCratio in both males and females decreases closer to full knee extension and with increasing movement velocity. The H/QFUNCwas also significantly lower in females compared to males, irrespective of moment velocity and joint angle.
  
  
  CONCLUSIONS
  The findings of the current study reinforce the need to examine the H/QFUNCratio closer to full knee extension (where knee injury is most likely to occur) rather than using PT values which may not be as informative, as well as to focus preventive and rehabilitation training programmes on reducing quadriceps dominance by enhancing eccentric hamstring strength (especially in females who are at higher risk of injury).
  
  
  METHODS
  III.
authors.affiliation: Faculty of Physical Education, Mansoura University, Mansoura, Egypt.
authors.forename: Said
authors.initials: S
authors.lastname: El-Ashker
authors.affiliation: Physical Education and Sport Sciences, University of Limerick, Limerick, Ireland.
authors.forename: Brian P
authors.initials: BP
authors.lastname: Carson
authors.affiliation: Sports Research Centre, Miguel Hernández University of Elche, Avda. de la Universidad s/n, 03202, Elche, Alicante, Spain. Franciscoayalarodriguez@gmail.com.|ISEN University Formation, Centre Affiliate to the University of Murcia, Murcia, Spain. Franciscoayalarodriguez@gmail.com.
authors.forename: Francisco
authors.initials: F
authors.lastname: Ayala
authors.affiliation: Faculty of Sport, Health and Social Care, School of Physical Education, University of Gloucestershire, Gloucester, UK.
authors.forename: Mark
authors.initials: M
authors.lastname: De Ste Croix
mesh_terms: D000328:Adult; D005260:Female; D000070633:Hamstring Muscles / Q000502:physiology*; D006801:Humans; D007719:Knee Joint / Q000502:physiology*; D008297:Male; D053580:Muscle Strength / Q000502:physiology*; D052097:Quadriceps Muscle / Q000502:physiology*; D016059:Range of Motion, Articular / Q000502:physiology; D012737:Sex Factors; D019415:Torque
keywords: Anterior cruciate ligament; Injury prevention; Isokinetic; Strength; Torque