Effects of vastus medialis oblique-focused and general quadriceps strengthening exercises on Q-angle and quadriceps strength in overweight and obese females: A randomized controlled trial

Article Sidebar

pdf
Published: Oct 29, 2026
DOI: https://doi.org/10.66285/JAMS.2027.020
Keywords:
Q-angle, quadriceps, vastus medialis oblique, strength

Main Article Content

Somruthai Poomsalood
Department of Physical Therapy, School of Allied Health Sciences, University of Phayao, Phayao, Thailand.
https://orcid.org/0000-0001-6486-9045
Panida Hanphitakphong
Department of Physical Therapy, School of Allied Health Sciences, University of Phayao, Phayao, Thailand.
https://orcid.org/0009-0002-7229-8398
Palagon Udomkichpagon
Department of Physical Therapy, School of Allied Health Sciences, University of Phayao, Phayao, Thailand.
https://orcid.org/0000-0001-6006-5779
Chatchadaporn Jaiyen
Department of Physical Therapy, School of Allied Health Sciences, University of Phayao, Phayao, Thailand.
https://orcid.org/0009-0004-4793-5708
Chayanid Wongchanta
Department of Physical Therapy, School of Allied Health Sciences, University of Phayao, Phayao, Thailand.
https://orcid.org/0009-0004-8172-2562
Natthaphon Chanrak
Department of Physical Therapy, School of Allied Health Sciences, University of Phayao, Phayao, Thailand.
https://orcid.org/0009-0009-8739-8202
Vasita Cheeprem
Department of Physical Therapy, School of Allied Health Sciences, University of Phayao, Phayao, Thailand.
https://orcid.org/0009-0003-7902-8726

Abstract

Background: Genu valgum is a condition characterized by an abnormal angling of the knee joints, causing the knees to tilt inward and the feet to rotate outward. This condition is commonly observed in overweight individuals, particularly females, due to abnormalities in body structure and muscle function, specifically in the quadriceps and vastus medialis obliquus (VMO) muscles. Such abnormalities can affect the Q-angle, and an increased Q-angle may lead to patellar instability and stress on the knee joint. Previous studies have indicated that exercises aimed at strengthening the quadriceps and VMO muscles can help reduce the Q-angle.


Objectives: This study aimed to compare the effects of VMO-focused strengthening exercises and general quadriceps strengthening exercises on the Q-angle and quadriceps strength in females with overweight and obesity.


Materials and methods: Twenty females with overweight and obesity were randomly divided into two groups of 10. The first group participated in an exercise program focused on strengthening VMO muscle, while the second group engaged in a program aimed at improving quadriceps strength. Both programs lasted for 4 weeks and were conducted 3 days a week. Measurements of the Q-angle and quadriceps muscle strength were taken one week prior to the start of the exercises and again after the completion of the 4-week program. Data were analyzed using a two-way mixed analysis of variance (ANOVA) to examine the effects of group (VMO vs. quadriceps) and time (pre- vs post-).


Results: The mixed ANOVA revealed no significant group × time interactions for Q-angle or quadriceps strength (all p>0.05). Both groups demonstrated similar patterns of change over time, with descriptive data indicating reductions in Q-angle and increases in quadriceps strength following the intervention.


Conclusion: Both VMO-focused and general quadriceps strengthening exercises produced similar changes in Q-angle and quadriceps strength over the 4-week intervention period. No significant differences were observed between the two exercise approaches. These results should be interpreted with caution because of the short intervention duration. Future studies employing longer training periods and more objective measures of muscle activation are warranted to better elucidate potential differences between exercise types and to strengthen the evidence base in this area.

Article Details

How to Cite
Poomsalood, S., Hanphitakphong, P., Udomkichpagon, P., Jaiyen, C., Wongchanta, C., Chanrak, N., & Cheeprem, V. (2026). Effects of vastus medialis oblique-focused and general quadriceps strengthening exercises on Q-angle and quadriceps strength in overweight and obese females: A randomized controlled trial. Journal of Associated Medical Sciences, 60(1), 215–225. https://doi.org/10.66285/JAMS.2027.020
Issue
Vol. 60 No. 1 (2027): January-April
Section
Research Articles
Creative Commons License

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Personal views expressed by the contributors in their articles are not necessarily those of the Journal of Associated Medical Sciences, Faculty of Associated Medical Sciences, Chiang Mai University.

References

[1] Loudon JK. Biomechanics and pathomechanics of the patellofemoral joint. Int J Sports Phys Ther. 2016; 11(6): 820-30.

[2] Boling MC, Padua DA, Marshall SW, Guskiewicz K, Pyne S, Beutler A. A prospective investigation of biomechanical risk factors for patellofemoral pain syndrome: the joint undertaking to monitor and prevent ACL injury (JUMP-ACL) cohort. Am J Sports Med. 2009; 37(11): 2108-16. doi: 10.1177/0363546509337934.

[3] Mizuno Y, Kumagai M, Mattessich SM, Elias JJ, Ramrattan N, Cosgarea AJ, et al. Q-angle influences tibiofemoral and patellofemoral kinematics. J Orthop Res. 2001; 19(5): 834-40. doi: 10.1016/S0736-0266(01)00008-0.

[4] Vanzeli CHG, Reis ACF, Pereira AG, Tavares MR, Fazan VPS. Measurement the “Q” angle through the application of direct method and indirect method. J Morphol Sci. 2016; 33(3): 168-70. doi: 10.4322/jms.079515.

[5] Vijayakumar K, Dineshkumar D. Effects of therapeutic weight loss exercises on obese individuals with genu valgum deformity. Indian J Public Health Res Dev. 2020; 11(9): 185-9. doi: 10.37506/ijphrd.v11i9.11007.

[6] Soheilipour F, Pazouki A, Mazaherinezhad A, Yagoubzadeh K, Dadgostar H, Rouhani F. The prevalence of genu varum and genu valgum in overweight and obese patients: assessing the relationship between body mass index and knee angular deformities. Acta Biomed. 2020; 91(4): e2020121. doi: 10.23750/abm.v91i4.9077.

[7] Elhoseny HA, Eltohamy AM, Diab OA. Effect of body mass index on quadriceps angle and tibial torsion in school-aged children. Bull Fac Phys Ther. 2024; 29: 76. doi: 10.1186/s43161-024-00235-1.

[8] Santhi V, Rajesh B. A study on the effect of isometric quadriceps activation and vastus medialis obliquus strengthening in decreasing q-angle among young females. J Evol Med Dent Sci. 2020; 9(12): 965-8. doi: 10.14260/jemds/2020/208.

[9] Nguyen AD, Boling MC, Levine B, Shultz SJ. Relationships between lower extremity alignment and the quadriceps angle. Clin J Sport Med. 2009; 19(3): 201-6. doi: 10.1097/JSM.0b013e3181a38fb1.

[10] Raveendranath R, Nachiket S, Sujatha N, Priya R, Rema D. Bilateral variability of the quadriceps angle (Q angle) in an adult Indian population. Iran J Basic Med Sci. 2011; 14(5): 465-71.

[11] Powers CM. The influence of altered lower-extremity kinematics on patellofemoral joint dysfunction: a theoretical perspective. J Orthop Sports Phys Ther. 2003; 33(11): 639-46. doi: 10.2519/jospt.2003.33.11.639.

[12] Sharma R, Vaibhav V, Meshram R, Singh B, Khorwal G. A systematic review on quadriceps angle in relation to knee abnormalities. Cureus. 2023; 15(1): e34355. doi: 10.7759/cureus.34355.

[13] Mazidi M, Alizadeh MH, Rajabi R. The effects of one period of exercise therapy program on Q and popliteal angle in athletes with patellofemoral pain syndrome. J Res Rehabil Sci. 2011; 7(2): 217-24 (in Persian). doi: 10.22122/jrrs.v7i2.217.

[14] Clark DI, Downing N, Mitchell J, Coulson L, Syzpryt EP. Physiotherapy for anterior knee pain: a randomized controlled trial of exercise, taping, and education. BMJ. 2000; 320(7238): 792-5. doi: 10.1136/bmj.320.7238.792.

[15] Witvrouw E, Lysens R, Bellemans J, Cambier D, Vanderstraeten G. Open versus closed kinetic chain exercises for patellofemoral pain. Am J Sports Med. 2000; 28(5): 687-94. doi: 10.1177/03635465000280050801.

[16] Crossley KM, van Middelkoop M, Callaghan MJ, Collins NJ, Rathleff MS, Barton CJ, et al. Patellofemoral pain consensus statement. Br J Sports Med. 2016; 50(14): 844-52. doi: 10.1136/bjsports-2016-096384.

[17] Powers CM. The influence of abnormal hip mechanics on knee injury. J Orthop Sports Phys Ther. 2010; 40(2): 42-51. doi: 10.2519/jospt.2010.3337.

[18] Shelburne KB, Pandy MG. A musculoskeletal model of the knee for evaluating muscle and joint forces during gait. J Biomech. 1997; 30(2): 163-76. doi: 10.1016/S0021-9290(96)00119-4.

[19] Livingston LA, Mandigo JL. Bilateral Q-angle asymmetry and anterior knee pain syndrome. Clin Biomech. 1999; 14(1): 7-13. doi: 10.1016/S0268-0033(98)00054-2.

[20] Powers CM. The influence of altered lower-extremity kinematics on patellofemoral joint dysfunction: a theoretical perspective. J Orthop Sports Phys Ther. 2003; 33(11): 639-46. doi: 10.2519/jospt. 2003.33.11.639.

[21] Cowan SM, Bennell KL, Hodges PW, Crossley KM, McConnell J. Delayed onset of electromyographic activity of vastus medialis obliquus relative to vastus lateralis in subjects with patellofemoral pain syndrome. Arch Phys Med Rehabil. 2001; 82(2): 183-9. doi: 10.1053/apmr.2001.19022.

[22] Crossley K, Cowan SM, Bennell KL, McConnell J. Patellar taping: is clinical success supported by scientific evidence? Man Ther. 2000; 5(3): 142-50. doi: 10.1054/math.2000.0233.

[23] Dogra K, Singh A. Correlation of Q-angle with muscle strength and balance parameters. Int J Med Pharm Res. 2025; 6(5): 196-200. doi: 10.5281/zenodo.17190708.

[24] Mrityunjay K, Chhabra D. Comparison between effect of isometric quadriceps exercise and vastus medialis oblique strengthening on quadriceps angle and patellar shift in normal individuals. Eur Acad Res. 2014; 2(4): 5360-70.

[25] WHO Expert Consultation. Appropriate body-mass index for Asian populations and its implications for policy and intervention strategies. Lancet. 2004; 363(9403): 157-63. doi: 10.1016/S0140-6736(03)15268-3.

[26] Weiss L, DeForest B, Hammond K, Schilling B, Ferreira L. Reliability of goniometry-based Q-angle. PM R. 2013; 5(9): 763-8. doi: 10.1016/j.pmrj.2013.03.023.

[27] Khasawneh RR, Allouh MZ, Abu-El-Rub E. Measurement of the quadriceps (Q) angle with respect to various body parameters in young Arab population. PLoS One. 2019; 14(6): e0218387.doi: 10.1371/journal.pone.0218387.

[28] Rousseau AF, Dardenne N, Kellens I, Bornheim S, Misset B, Croisier JL. Quadriceps handheld dynamometry during the post-ICU trajectory: using strictly the same body position is mandatory for repeated measures. Intensive Care Med Exp. 2023; 11(1): 39. doi: 10.1186/s40635-023-00523-5.

[29] Slater LV, Hart JM. Muscle activation patterns during different squat techniques. J Strength Cond Res. 2017; 31(3): 667-76. doi: 10.1519/JSC.0000000000001323.

[30] Ferber R, Bolgla L, Earl-Boehm JE, Emery C, Hamstra- Wright K. Strengthening of the hip and core versus knee muscles for the treatment of patellofemoral pain: a multicenter randomized controlled trial. J Athl Train. 2015; 50(4): 366-77. doi: 10.4085/1062-6050-49.3.70.

[31] Muyor JM, Martín-Fuentes I, Rodríguez-Ridao D, Antequera-Vique JA. Electromyographic activity in the gluteus medius, gluteus maximus, biceps femoris, vastus lateralis, vastus medialis and rectus femoris during the monopodal squat, forward lunge and lateral step-up exercises. PLoS One. 2020; 15(4): e0230841. doi: 10.1371/journal.pone.0230841.

[32] Kushion D, Rheaume J, Kopchitz K, Glass S, Alderink G, Jinn J. EMG activation of the vastus medialis oblique and vastus lateralis during four rehabilitative exercises. Open Rehabil J. 2012; 5: 1-7. doi: 10.2174/1874943701205010001.

[33] Shabick MA, Latip HFM, Aziz MSA. Exercises to increase vastus medialis oblique activity: a review. J Sport Games. 2019; 1(2): 18-22. doi: 10.22259/2642-8466.0102004.

[34] O’Sullivan SP, Popelas CA. Activation of vastus medialis obliquus among individuals with patellofemoral pain syndrome. J Strength Cond Res. 2005; 19(2): 302-4. doi: 10.1519/1533-4287(2005)19[302:AOVMOA]2.0.CO;2.

[35] Cho M, Kang JY, Oh JH, Wu JG, Choi EB, Park SE, et al. The effects of performing squats on an inclined board on thigh muscle activation. Phys Ther Rehabil Sci. 2017; 6(1): 39-44. doi: 10.14474/ptrs.2017.6.1.39.

[36] Lee S, Park J, Lee D. Effects of bridge exercise performed on an unstable surface on lumbar stabilizing muscles according to the knee angle. J Phys Ther Sci. 2015; 27(8): 2633-5. doi: 10.1589/jpts.27.2633.

[37] Earl JE, Hoch AZ. A proximal strengthening program improves pain, function, and biomechanics in women with patellofemoral pain syndrome. Am J Sports Med. 2011; 39(1): 154-63. doi: 10.1177/0363546510379967.

[38] Livingston LA. The quadriceps angle: a review of the literature. J Orthop Sports Phys Ther. 1998; 28(2): 105-9. doi: 10.2519/jospt.1998.28.2.105.

[39] Herrington L, Nester C. Q-angle undervalued? The relationship between Q-angle and medio-lateral position of the patella. Clin Biomech. 2004; 19(10): 1070-3. doi: 10.1016/j.clinbiomech.2004.07.006.

[40] Syme G, Rowe P, Martin D, Daly G. Disability in patients with chronic patellofemoral pain syndrome: a randomised controlled trial of a home exercise programme. Knee. 2009; 16(3): 223-9. doi: 10.1016/j.knee.2008.11.002.

[41] Fukuda TY, Rossetto FM, Magalhães E, Bryk FF, Lucareli PRG, de Almeida Aparecida Carvalho N. Short-term effects of hip abductors and lateral rotators strengthening in females with patellofemoral pain syndrome: a randomized controlled clinical trial. J Orthop Sports Phys Ther. 2010; 40(11): 736-42. doi: 10.2519/jospt.2010.3246.

[42] Kraemer WJ, Ratamess NA. Fundamentals of resistance training: progression and exercise prescription. Med Sci Sports Exerc. 2004; 36(4): 674-88. doi: 10.1249/01.MSS.0000121945.36635.61.

[43] Folland JP, Williams AG. The adaptations to strength training: morphological and neurological contributions to increased strength. Sports Med. 2007; 37(2): 145-68. doi: 10.2165/00007256-200737020-00004.

[44] Irish SE, Millward AJ, Wride J, Haas BM, Shum GLK. The effect of closed-kinetic chain exercises and open-kinetic chain exercise on the muscle activity of vastus medialis oblique and vastus lateralis. J Strength Cond Res. 2010; 24(5): 1256-62. doi: 10.1519/JSC.0b013e3181d32c11.

[45] Smith TO, Nichols R, Harle D, Donell ST. Do the vastus medialis obliquus and vastus lateralis differ in function in patients with patellofemoral pain syndrome? A systematic review. Knee. 2009; 16(4): 301-8. doi: 10.1016/j.knee.2008.09.002.

[46] Bolgla LA, Uhl TL. Electromyographic analysis of hip rehabilitation exercises in a group of healthy subjects. J Orthop Sports Phys Ther. 2005; 35(8): 487-94. doi: 10.2519/jospt.2005.35.8.487.

[47] Kraemer WJ, Ratamess NA, French DN, Volek JS, Häkkinen K, Rubin MR, et al. Physiological adaptations to resistance exercise. Sports Med. 2002; 32(7): 467-83. doi: 10.2165/00007256-200232070-00004.

[48] Schoenfeld BJ. The mechanisms of muscle hypertrophy and their application to resistance training. J Strength Cond Res. 2010; 24(10): 2857-72. doi: 10.1519/JSC.0b013e3181e840f3.

[49] Dolak KL, Silkman C, Medina McKeon J, Hosey RG, Lattermann C, Uhl TL. Hip strengthening prior to functional exercises reduces pain sooner than quadriceps strengthening in females with patellofemoral pain syndrome. J Orthop Sports Phys Ther. 2011; 41(8): 560-70. doi: 10.2519/jospt.2011.3554.

[50] American College of Sports Medicine. Progression models in resistance training for healthy adults. Med Sci Sports Exerc. 2009; 41(3): 687-708. doi: 10.1249/MSS.0b013e3181915670.