The Effect of Fatigue on Peak Vertical Ground Reaction Force in Women with Different Knee Alignments during Single-Leg Jump and Drop Landing

Document Type: Research Paper


1 MSc, Department of Corrective Exercises and Sport Injury, Faculty of Physical Education, Kharazmi University, Tehran, Iran

2 Associate Professor of Corrective Exercises and Sports Injuries, Kharazmi University of Tehran, Iran


Deviation from the standard alignment of knee joint may changes weight distribution procedure and therefore reduces the mechanical efficiency. Understanding the biomechanical changes resulting from these deformities during fatigue is an important step in the prevention of subsequent injuries. So, the aim of this study was to investigate the effect of fatigue on peak vertical ground reaction force during single-leg drop landing in women with genu varum, genu valgum and normal knee. 40 healthy female students of physical education and sport sciences with genu varum deformity (n=14), genu valgum deformity (n=14) and normal knee (n=12) participated in this study. Caliper was used to assess alignment of knee and the subjects were divided into three groups (genu varum, genu valgum and normal knee). Then, subjects performed single-leg drop landing from 50% of maximum sergeant jump onto the force platform. After the fatigue protocol, jump-drop landing task was measured and recorded again. Analysis of variance with repeated measures was used for within-group comparison. The peak vertical ground reaction force was not significant in women with different knee alignments (P=0.314) and also fatigue had no significant difference in this variable (P=0.479). According to these results, it seems that fatigue (according to the protocol in this study) could not change vertical ground reaction force in those subjects with different knee alignments which paves the way for further research with different fatigue protocols.


1.Gharakhanlou R, Alizadeh M h, Daneshmandi H. Corrective Exercises. 2nd  ed. Tehran, SAMT & Sport Sciences Research Institute; 2004.
2.Shojadin S, Johari K, Sadeghi H. The Effect of the Fatigue in Lower Extremity Proximal and Distal Muscles on Dynamic Balance in Male Soccer Players (In Persian). Journal of sport medicine. 2011;2(2): 65-80.

3.Stroebel S, De Redder JH, Wilders CJ, Ellis S M. Differences in body composition and prevalence for postural deviations in girls from two racial groups in South Africa. South African Journal for Research in Sport, Physical Education and Recreation. 2009; 31(2): 119-33.

4.Shahamiri Fatahi F, Alizadeh MH, Minoonejad H. Effect of Genu Varum Deformity on Dynamic Stabilization during Single-Leg Jump-Landing (In Persian). 2013;5(13):39-52.

5.Chao E Y, Neluheni E V, Hsu R W, Paley D. Biomechanics of malalignment. Orthopedic Clinics of North America. 1994; 25(3):  379-86.

6. Malinzak R A, Colby S M, Kirkendall D T, Yu B, Garrett WE. A comparison of knee joint motion patterns between men and women in selected athletic tasks. Clinical Biomechanics. 2001, 16(5): 444-83.

7. Dufek J S, Bates B T.Biomechanical factors associated with injury during landing in jump sportsSports Medicine. 1991; 12(5): 326-37.

8. McNair P J, Prapavessis H, Callender K. Decreasing landing forces: effect of instruction. British Journal of Sport Medicine. 2000;  34(4): 293-296.
9. Letafatkar A, Daneshmandi H, Hadadnezhad M. Abdolvahabi Z. Advanced Corrective Exercises( From theory to Application). Thran, Avaye Zohor; 2011.
10. McNitt Gray JL. Kinematics and impulse characteristics of drop landings from three heights. Human kinetics Journals. 1991; 7(2): 201-24.
11.Nyland J, Smith S, Beickman K, Armsey T, Caborn DN. Frontal plane knee angle affects dynamic postural control strategy during unilateral stance. Medicine & Science in Sports & Exercise . 2002; 34(7): 1150-7.
12. Hrysomallis C, Goodman C. A review of resistance exercise and posture realignment. The Journal of Strength & Conditioning Research . 2001; 15(3): 385-90.
13. . Cammarata ML, Dhaher YY. The differential effects of gender , anthropometry and prior hormonal state on frontal plane knee joint stiffness. Clinical Biomechnics 2008;23: 937-945.
14. Boden B P, Dean G S, Feagin J A, Garrett W E. Mechanisms of anterior cruciate ligament injury. Orthopedics. 2000; 23: 573-78.
15. Robert A,Maliinzak S M, Colby D,T.kirkendall B Yu William E. Acomparison of knee joint motion patterns between men and women in selected athletic tasks. Clinical Biomechanics. 2001; 16(5) 438-445.
16. Boham M ,deBeliso M, harris Ch, Pfeiffer R, McChesney J , Berning J.M. The effects of functional fatigue on ground reaction force of a jump, land, and cut task. Science and Engineering Investigations. 2013;2(21): 22-28.
17. Chappell JD, Herman DC, Knight BS. Kirkendal DT, Garrett WE, Yu B. Effect of fatigue on knee kinetics and kinematics in stop – jump tasks. The American Journal of Sports Medicine. 2005;33(7):1022-9.
18. Pappas E, Sheikhzadeh A, Hagins M, Nordin M. The effect of gender and fatigue on the biomechanics of bilateral landings from a jump: Peak values. Journal of Sports Science and Medicine. 2007;6:77-84.
19. Devita P, Skelly W A. Effect of landing stiffness on joint kinetics and energetics in the lower extremity.  Medicine & Science in Sports & Exercise. 1992; 24(1): 108-15.

20. Yeow C H, Lee P V, Goh JC. An investigation of lower extremity energy dissipation strategies during single-legand double-leg landing based on sagittal and frontal plane biomechanics. Human Movement Science. 2011; 30(3): 624-35.

21. Alizadeh M H, Gheytasi M. Fundamental Concepts of Corrective exercises. Tehran.Sport Sciences Research Institute. 2013.
22. Shiekh Saraf b. The Influence of Gender on Knee Kinematics During Landing and Cutting [MSc]. Tarbiat Moalem University;2008.
23. Bakhtiary A H, Fatemi E, Rezasoltani A.Genu varum deformity may increase postural sway and falling risk. koomesh. 2012;13(3):330 - 7.
24. MahakiM, ShojaedinS,MemarR,Mahaki B. [The Comparsion of the Electromyography of Leg Muscles and Peak Vertical Ground Reaction Forces during Single Leg Drop Landing between Men with Genu Varum Deformity and Normal Knee(IN Persian)].Bimonthly journal of research in rehabilitation sciences.2014;8(3):61-70.

25. Bonacci J, Vleckc V, Saundersd PU, Blanchb P, Vicenzinoe B. Rating of perceived exertion during cycling is associated with subsequent running economy in triathletes. Journal of Science and Medicine in Sport. 2013; 16: 49–53.

26. Winter DA. Biomechanics and motor control of human movement. 4th ed. John Wily & Sons, Inc; 2009.
27. Bauer JJ, Fuchs RK, Smith GA, Snow CM. Quantifying force magnitude and loading rate from drop landings that induce osteogenesis. Human Kinetics Journals . 2001; 17(2): 142-52.
28. Shahamiri Fatahi F, Alizadeh MH, Minoonejad H. Effect of Genu Varum Deformity on Dynamic Stabilization during Single-Leg Jump-Landing (In Persian). Sport Medicine Studies. 2013;5(13):39-52.
29. Cappozzo A. The mechanics of human walking. International Journal of Applied Physics. 1991; 78: 167-86.
30. Decker M J, Torry M R, Wyland D J, Sterett W I, Richard S J. Gender differences in lower extremity kinematics, kinetics and energy absorption during landing . Clinec Biomechanic (Bristol, Avon) 2003; 18(7): 662-9.
31. Zhang SN, Bates BT, Dufek JS. “Contributions of lower extremity joints to energy dissipation during landings”.

Medicine & Science in Sports & Exercise 

 2000; 32(4): 812-9.
32. Junge A, Dvorak J. Soccer injuries: a review on incidence and prevention. Sports Medicen. 2004; 34(13): 929-38.
33. Nyland J, Smith S, Beickman K, Armsey T, Caborn DN. “Frontal plane knee angle affects dynamic postural control strategy during unilateral stance.  Medicine & Science in Sports & Exercise. 2002; 34(7): 1150-7.
34. Melissa D H, Christopher R C, Bruce M G, Sandra J S h. Subtalar Pronation Does Not Influence Impact Forces or Rate of Loading During a Single-Leg Landing. Journal of athletic training. 2003;38(1):18–23.
35. Yayaei-Rad M, Norasteh A A , Shamsi A, Sanjari M A. The Comparison of Postural Stability in Different Knee Alignment. Journal of Basic and Applied Scientific Research. 2013; 3(7): 322-326.
36. Abbasi A,Sadeghi H, Khaleghi Tzji M, Hoseynimehr S H. Gender differences in attraction of Ground reaction forces in Jump and landing(In Persian).Journal of Olympic. 2010;4(48):83-92.