The Effect of Fatigue Induced by Exhaustive Exercises on Dynamic Balance and Balance Recovery Time in Active Men with Genu Varum and Normal Knee

Document Type : Research Paper


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

2 -Associate Professor, Department of Corrective Exercises and Sports Injury, Faculty of Physical Education and Sport Sciences, Kharazmi University, Tehran, Iran


Balance plays a key role in daily and sports activities. The aim of this study was to investigate the effect of fatigue induced by exhaustive exercises on dynamic balance and balance recovery time in active men with genu varum and normal knee. 40 active healthy male students including 20 subjects with genu varum deformity and 20 normal subjects participated in this semi-experimental study. Genu varum deformity was assessed with a caliper and a goniometer. Strand test was used to create fatigue. SPSS software and statistical tests of analysis of combined variance within-between groups, t test and paired t test were used to analyze data. The results of the mean dynamic balance index by paired t test showed that this index increased significantly in the posttest and pretest comparison in both groups (P=0.00). However, independent t test showed that the mean of these changes was not significantly different between the groups (P=0.56). The dynamic balance index in both groups was fully recovered 10 minutes after fatigue. Medial displacement of the gravity line could increase the lateral posture sways in subjects with genu varum and since this deformity causes internal rotation of the leg and pronation of the subtalar joint in weight-bearing condition, leg structure changes can change leg function to control balance.


1. Ageberg E, Robert D, Holmstorm E, Friden T.(2003). "Balance in single-limb stance in healty subjects – reliability of testing procedure and the effect short duration sub-maximal cycling". Journal of foot and ankle research. 4(14); PP: 1-16.
2. Anker LC, Weerdesteyn V, van Nes IJ, Nienhuis B, Straatman H, Geurts AC.(2008)."The relation between postural stability and weight distribution in healthy subjects". Journal of  Gait Posture. 27; PP: 471-477.
3. Baker AJ, Kostov KG, Miller RG, Weiner MW.(1993). "Slow force recovery after long duration exercise: metabolic and activation factors in muscle fatigue". Journal of  appl physiol. 74; PP: 2294-2300.
4. Bove M, Faelli E, Tacchino A, Lofrano F, Cogo CE, Ruggeri P.(2007). "Postural control after a strenuous treadmill exercise". Journal of Neuroscience letters. 418(3); PP: 276-281 .
5. Burdet C, Rougier P.(2004). "Effect of utmost fatigue on undisturbed upright stance control". Journal of  Science& Sport. 19; PP: 308-316.
6. Cobb SC, Tis LL, Johnson BF, Higbie EJ.(2004). "The effect of fore foot varus on postural stability". Journal of  Orthop Sports PhysTher. 34; PP: 79-85.
7. Emery C, Tyreman H.(2009). "Sport participation, sport injury, risk factors and sport safety practices in Calgary and area junior high schools". Journal of  Paediatr Child Health. 14; PP: 439-444.
8. Fox CR, Paige GD.(1991). "Effect of head orientation on human postural stability following unilateral vestibular". Journal of Vestib Res. 1(2); PP: 153-160.
9. Gribble P, Hertel J.(2003). "Considerations for the normalizing measures of the star excursion balance test". Journal of  Measur Phys Educ Exer Sci. 7; PP: 89-100.
10. Hadadnezhad M, Letafatkar A.(2011). "The relationship between genu varum abnormality and lower extremity's performance and strength in teenage footballers". Journal of Rehabil Sci. 7(2); PP: 188-96.
11. Harkins KM, Mattacola CG, Uhl TL, Malone TR, McCrory JL.(2005). "Effects of 2 ankle fatigue model on the duration of postural dysfunction". Journal of Athl Train. 40(3); PP: 191-194.
12. Hobbs, M. L.(2008). "Dynamic Balance and Basketball Playing Ability". Theses and Dissertations-Health and Human Performance. PP:1-129.
13. Horak FB.(1987). "Clinical measurement of postural control in adults". Journal of  Phys Ther. 67; pp: 1881-1885.
14. Hrysomallis C, McLaughlin P, Goodman C.(2007). "Balance and injury in elite Australian footballers". Int Journal of  Sports Med. 28; PP: 844-847.
15. Khanna P , Gagan K , Zutshi K.(2008). "Balance deficits and recovery timeline after different fatigue protocols". Indian journal of physiotherapy and occupational therapy. 2(3); PP: 42- 54.
16. Lepers R, Bigard AX, Diard JP, Guezennec CY.(1997). "posture control after prolonged exercise". Enr Journal of Appl Physiol. 76(1); PP: 55-61 .
17. Levangie PK, Norkin CC.(2005). "Joint structure & function". F.A Davis Company. Hardcover.  4 edition th; PP: 1-588.
18. Nardone A, Tarantola J,Giorano A, Schiepatti M.(1997). "Fatigue effects on body balance" . Journal of  Electoencephalogr Clin Neurophysol. 105; PP: 309-320.
19. Olmsted L, Hertel J.(2004). "Influence of foot type and orthotics on static and dynamic postural control". Journal of  Sport Rehabil. 13; PP: 54-66.
20. Punakallio A.(2005). "Balance abilities of workers in physically demanding  jobs, With special reference to firefighters of different ages". Journal of Sports Sci & Med. 4; PP: 7-14.
21. Reimer R, Wikstrom E.(2010). "Functional fatigue of the hip and ankle musculature cause similar alterations in single leg stance postural control". Journal of Science and Medicine in Sport. 13; PP: 161 – 166.
22. Samaei A, Bakhtiary AH, Elham F, Rezasoltani A.(2012). "Effects of genu varum deformity on postural stability". Journal of Sports Med. 33(6); PP: 469-473.
23. Sendur OF, Gurer G, Yildirim T, Ozturk E, Aydeniz A. (2006). "Relationship of Q angle and joint hypermobility and Q angle values in different positions". Journal of  Clin Rheumatol. 25; PP: 304–308.
24. Sharma L, Song J, Dunlop D, Felson D, Lewis CE, Segal N, et al.(2010). "Varus and valgus alignment and incident and progressive knee osteoarthritis". Journal of  Ann Rheum Dis. 69(11); PP: 1940-1945.
25. Simoneau M, Begin F, Teasdale N.(2006). "The effecte of moderate fatigue on dynamic balance control and attentional demands". Journal of neuroengineering and rehabilitation. 3(22); PP: 1-9.
26. Susco T, Valovich MLT, Gansneder B, Shults S.(2004). "Balance recovers within 20 minutes after exertion as measured by the balance error scoring system".  Journal of Athl Train. 39(3); PP: 241-246 .
27. Van GB, Kirby KA, Hagman F.(2005). "Effects of simulated genu valgum and genu varum on ground reaction forces and subtalar joint function during gait". Journal of  Am Podiatric Med Assoc. 95(6); PP: 531-541.
28. Wilkins JC, Leod TCV, Perrin DH, Gansneder BM.(2004). "Performance on the balance errore scoring system decreases after fatigue". Journal of athletic training. 39(2); PP: 152-161.
29. Williams DS, Mcclay IS, Hamill J, Buchanan TS.(2001). "Lower extremity kinematics and kinetics differences in runners with high and low arches". Journal of Appl Biomech. 17; PP: 153-163.
30. Yaggie J, Armstrong WJ.(2004). "Effect of lower extremity fatigue on indices of balance". Journal of Sport Rehabil. 13(4); PP: 312-322.
31. Yaggie J, McGregor SJ.(2002). "effects of isokinetic ankle fatigue on the maintenance pf balance and postural limits". Journal of  Arch Phys med rehab. 83(2); PP: 224-228.
32. Zech A, Hubscher M, Vogt L, Banzer W, Hansel F, Pfeifer K.(2010). "Balance training for neuromuscular control and performance enhancement : a systematic review". Journal of Athl Train. 45; PP: 392-403.
33. Zemkova E, Hamar D.(2009). "The effect of soccer match induced fatigue on neuromuscular performance". Journal of Kinesiology. 41(2); PP: 195-202.