Research Article
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Subtalar joint pronation: Which is the real concern-presence or severity? A cross-sectional study

Year 2024, , 169 - 177, 30.09.2024
https://doi.org/10.31459/turkjkin.1535023

Abstract

The study aims to compare static and dynamic postural stability, navicular drop, dorsiflexion range of motion, and jumping performance of individuals with neutral, prone, and hyperprone foot postures. Forty-eight participants between the ages of 18 and 40, were categorized into neutral (n=16), prone (n=16), and hyperprone (n=16) according to foot posture index (FPI). Static and dynamic postural control evaluations (with the Biodex Balance System SD), navicular drop test (NDT) weight-bearing lunge test, countermovement jump test without arm swing, and drop vertical jump tests have been completed. In the results, the average age of participants in the NG, PG, and HPG are 22.31 ± 2.75, 23.87± 3.72, and 22.37 ± 1.28 years and BMI are 22.6 ± 3, 23.4 ± 3.8, and 21.4 ± 2.24 (kg/m²), respectively. The demographic data of the participants showed a homogeneous distribution. There were no significant differences in none of the outcomes except the NDT. Navicular drop amount is positively correlated by the subtalar joint pronation. An increase in subtalar joint pronation does not have a significant effect on static and dynamic stability, jump performance, or dorsiflexion range of motion in healthy individuals.

Ethical Statement

Araştırma için etik kurul olayı çalışma başlamadan alınmıştır. Çalışma esnasında etik hiçbir ihlal yapılmamıştır. Yazarların hiç kimse ile veya hiçbir kuruluş ile çıkar çatışması yoktur.

Supporting Institution

Bahçeşehir Üniveristesi laboratuvarındaki malzemeler kullanılmıştır. Destekleyen kuruluş yoktur.

Thanks

We would like to thank Emirhan Koçer and Semra Karaçomak for their support.

References

  • Akbari, H., Kuwano, S., & Shimokochi, Y. (2023). Effect of heading a soccer ball as an external focus during a drop vertical jump task.  Orthop J Sports Med, 11(4), 23259671231164706.
  • Almansoof, H. S., Nuhmani, S., & Muaidi, Q. (2023). Role of ankle dorsiflexion in sports performance and injury risk: A narrative review. Electron J Gen Med, 20(5), em521.
  • Angın, S., Ilçin, N., Yeşilyaprak, S. S., & Simşek, I. E. (2013). Prediction of postural sway velocity by foot posture index, foot size and plantar pressure values in unilateral stance. Jt Dis Relat Surg, 24(3), 144-148.
  • Barton, C. J., Bonanno, D., Levinger, P., & Menz, H. B. (2010). Foot and ankle characteristics in patellofemoral pain syndrome: a case control and reliability study. J Orthop Sports Phys Ther, 40(5), 286-296.
  • Bayıroğlu, G., Pisirici, P., & Feyzioğlu, Ö. (2024). The effect of different subtalar joint pronation amounts on postural stability, function and lower extremity alignment in healthy individuals. Foot (Edinb), 60, 102123.
  • Beard, D., & Refshauge, K. (2000). Effects of ACL reconstruction on proprioception and neuromuscular performance. Proprioception and neuromuscular control in joint stability. Philadelphia: Human Kinetics.
  • Bennell, K. L., Talbot, R. C., Wajswelner, H., Techovanich, W., Kelly, D. H., & Hall, A. J. (1998). Intra-rater and inter-rater reliability of a weight-bearing lunge measure of ankle dorsiflexion. Aust J Physiother, 44(3), 175-180.
  • Bobbert, M. F., Huijing, P. A., & van Ingen Schenau, G. J. (1987). Drop jumping. II. The influence of dropping height on the biomechanics of drop jumping. Med Sci Sports Exerc, 19(4), 339-346.
  • Bosco, C., Tarkka, I., & Komi, P. V. (1982). Effect of elastic energy and myoelectrical potentiation of triceps surae during stretch-shortening cycle exercise. Int J Sports Med, 3(3), 137-140.
  • Cobb, S. C., Bazett-Jones, D. M., Joshi, M. N., Earl-Boehm, J. E., & James, C. R. (2014). The relationship among foot posture, core and lower extremity muscle function, and postural stability. J Athl Train, 49(2), 173-180.
  • Cobb, S. C., Tis, L. L., Johnson, B. F., & Higbie, E. J. (2004). The effect of forefoot varus on postural stability. J Orthop Sports Phys Ther, 34(2), 79-85.
  • Cornwall, M. W., McPoil, T. G., Lebec, M., Vicenzino, B., & Wilson, J. (2008). Reliability of the modified Foot Posture Index. J Am Podiatr Med Assoc, 98(1), 7-13.
  • Cote, K. P., Brunet, M. E., Gansneder, B. M., & Shultz, S. J. (2005). Effects of Pronated and Supinated Foot Postures on Static and Dynamic Postural Stability. J Athl Train, 40(1), 41-46.
  • David, E., Joseph, B., Mohammad, H., Joseph, M., & Elina, S. (2020). Correlation of navicular drop to vertical and broad jump measurements in young adults. J Rehab Therapy, 2, 1-5. Glatthorn, J. F., Gouge, S., Nussbaumer, S., Stauffacher, S., Impellizzeri, F. M., & Maffiuletti, N. A. (2011). Validity and reliability of Optojump photoelectric cells for estimating vertical jump height. J Strength Cond Res, 25(2), 556-560.
  • Goldie, P. A., Bach, T. M., & Evans, O. M. (1989). Force platform measures for evaluating postural control: reliability and validity. Arch Phys Med Rehabil, 70(7), 510-517.
  • Hertel, J., Gay, M. R., & Denegar, C. R. (2002). Differences in postural control during single-leg stance among healthy individuals with different foot types. J Athl Train, 37(2), 129-132.
  • Hoch, M. C., & McKeon, P. O. (2011). Normative range of weight-bearing lunge test performance asymmetry in healthy adults. Man Ther, 16(5), 516-519.
  • Hsieh, R. L., Peng, H. L., & Lee, W. C. (2018). Short-term effects of customized arch support insoles on symptomatic flexible flatfoot in children: A randomized controlled trial. Medicine (Baltimore), 97(20), e10655.
  • Hyong, I. H., & Kang, J. H. (2016). Comparison of dynamic balance ability in healthy university students according to foot shape. J Phys Ther Sci, 28(2), 661-664.
  • Jung, D. Y., Koh, E. K., Kwon, O. Y., Yi, C. H., Oh, J. S., & Weon, J. H. (2009). Effect of medial arch support on displacement of the myotendinous junction of the gastrocnemius during standing wall stretching. J Orthop Sports Phys Ther, 39(12), 867-874.
  • Ker, R. F., Bennett, M. B., Bibby, S. R., Kester, R. C., & Alexander, R. M. (1987). The spring in the arch of the human foot. Nature, 325(7000), 147-149.
  • Kim, J. A., Lim, O. B., & Yi, C. H. (2015). Difference in static and dynamic stability between flexible flatfeet and neutral feet. Gait Posture, 41(2), 546-550. Kısacık, P., Tunay, V. B., Bek, N., Atay, Ö. A., Selfe, J., & Karaduman, A. A. (2021). Short foot exercises have additional effects on knee pain, foot biomechanics, and lower extremity muscle strength in patients with patellofemoral pain. J Back Musculoskelet Rehabil, 34(6), 1093-1104. Koura, G. M., Elimy, D. A., Hamada, H. A., Fawaz, H. E., Elgendy, M. H., & Saab, I. M. (2017). Impact of foot pronation on postural stability: An observational study. J Back Musculoskelet Rehabil, 30(6), 1327-1332.
  • Kurtoğlu, A., Çar, B., Eken, Ö., Demir, G., Türkmen, M., Setiawan, E., Alotaibi, M. H., & Elkholi, S. M. (2024). Pes planus level affects counter movement jump performance: A study on amateur male and female volleyball players. Medicine, 103(25), e38683.
  • Letafatkar A, Zandi S, Khodayi M, Vashmesara J.B. (2013). Flat foot deformity, Q angle and knee pain are interrelated in wrestlers. J Nov Physiother, 3(2), 1000138.
  • Mohammadi, H. K., Mehravar, M., Kalantari, K. K., Naimi, S. S., Baghban, A. A., Okhovatian, F., Rezasoltani, A., Mohseni Bandpei, M. A., & Taheri, N. (2018). A comparison of foot kinetic parameters between pronated and normal foot structures during forward jump landing. J Bodyw Mov Ther, 22(3), 661-665.
  • Neal, B. S., Griffiths, I. B., Dowling, G. J., Murley, G. S., Munteanu, S. E., Franettovich Smith, M. M., Collins, N. J., & Barton, C. J. (2014). Foot posture as a risk factor for lower limb overuse injury: a systematic review and meta-analysis. J Foot Ankle Res, 7(1), 55.
  • Nguyen, A. D., & Shultz, S. J. (2007). Sex differences in clinical measures of lower extremity alignment. J Orthop Sports Phys Ther, 37(7), 389-398.
  • Nilstad, A., Andersen, T. E., Bahr, R., Holme, I., & Steffen, K. (2014). Risk factors for lower extremity injuries in elite female soccer players. Am J Sports Med, 42(4), 940-948.
  • Padua, D. A., Marshall, S. W., Boling, M. C., Thigpen, C. A., Garrett, W. E., Jr, & Beutler, A. I. (2009). The Landing Error Scoring System (LESS) is a valid and reliable clinical assessment tool of jump-landing biomechanics: The JUMP-ACL study. Am J Sports Med, 37(10), 1996-2002.
  • Pişirici, P., Ekiz, M. B., & İlhan, C. A. (2020). Investigation of the acute effect of myofascial release techniques and dynamic stretch on vertical jump performance in recreationally active individuals. Journal of Physical Education and Sport, 20(3), 1569-1579.
  • Raghav, U., Mahajan, R., & Khan, F. A. (2024). Correlation of over-pronated feet with static and dynamic balance among runners. Yugato, 76(1).
  • Ramani Hardik, A., Shukla, Y. U., & Gill, M. A. Correlation of pronated foot posture and vertical jump measurement in adolescent recreational basketball players-An observational study. International Journal of Science and Healthcare Research, 9(3), 6-12.
  • Rath, M. E., Stearne, D. J., Walker, C. R., & Cox, J. C. (2016). Effect of foot type on knee valgus, ground reaction force, and hip muscle activation in female soccer players. J Sports Med Phys Fitness, 56(5), 546-553.
  • Ribeiro, A. P., Trombini-Souza, F., Tessutti, V., Rodrigues Lima, F., Sacco, I. deC., & João, S. M. (2011). Rearfoot alignment and medial longitudinal arch configurations of runners with symptoms and histories of plantar fasciitis. Clinics (Sao Paulo, Brazil), 66(6), 1027-1033.
  • Sánchez-Ramírez, C., Aguado, X., Hormazábal-Aguayo, I., Alarcón, E., Sánchez-Ramírez, C., Aguado, X., & Alarcón, E. (2020). The relation of foot morphology to performance in three vertical jumping tasks. Int J Morphol, 38(3), 545-551.
  • Sattler, T., Sekulic, D., Hadzic, V., Uljevic, O., & Dervisevic, E. (2012). Vertical jumping tests in volleyball: reliability, validity, and playing-position specifics. J Strength Cond Res, 26(6), 1532-1538.
  • Singh, A., Sharma, M., & Mathur, G. R. (2023). Biomechanical analysis of countermovement jump performance among sports players with flatfoot and normal foot structures. Applied Biological Research, 25(1), 116-121. Tiberio D. (1988). Pathomechanics of structural foot deformities. Phys Ther, 68(12), 1840-1849.
  • Tong, J. W., & Kong, P. W. (2013). Association between foot type and lower extremity injuries: systematic literature review with meta-analysis. J Orthop Sports Phys Ther, 43(10), 700-714.
  • Tourillon, R., Six, A., Bothorel, H., & Fourchet, F. (2023). Are foot posture and morphological deformation associated with ankle plantar flexion isokinetic strength and vertical drop jump kinetics? A principal component analysis. Sports Biomech, 24, 1-15.
  • Tsai, L. C., Yu, B., Mercer, V. S., & Gross, M. T. (2006). Comparison of different structural foot types for measures of standing postural control. J Orthop Sports Phys Ther, 36(12), 942-953.
  • Wen, N., Dalbo, V. J., Burgos, B., Pyne, D. B., & Scanlan, A. T. (2018). Power testing in basketball: Current practice and future recommendations. J Strength Cond Res, 32(9), 2677-2691.
  • Yoon, K. S., & Park, S. D. (2013). The effects of ankle mobilization and active stretching on the difference of weight-bearing distribution, low back pain and flexibility in pronated-foots subjects. J Exerc Rehabil, 9(2), 292-297.
  • Zhao, X., Tsujimoto, T., Kim, B., & Tanaka, K. (2017). Association of arch height with ankle muscle strength and physical performance in adult men. Biol Sport, 34(2), 119-126.
Year 2024, , 169 - 177, 30.09.2024
https://doi.org/10.31459/turkjkin.1535023

Abstract

References

  • Akbari, H., Kuwano, S., & Shimokochi, Y. (2023). Effect of heading a soccer ball as an external focus during a drop vertical jump task.  Orthop J Sports Med, 11(4), 23259671231164706.
  • Almansoof, H. S., Nuhmani, S., & Muaidi, Q. (2023). Role of ankle dorsiflexion in sports performance and injury risk: A narrative review. Electron J Gen Med, 20(5), em521.
  • Angın, S., Ilçin, N., Yeşilyaprak, S. S., & Simşek, I. E. (2013). Prediction of postural sway velocity by foot posture index, foot size and plantar pressure values in unilateral stance. Jt Dis Relat Surg, 24(3), 144-148.
  • Barton, C. J., Bonanno, D., Levinger, P., & Menz, H. B. (2010). Foot and ankle characteristics in patellofemoral pain syndrome: a case control and reliability study. J Orthop Sports Phys Ther, 40(5), 286-296.
  • Bayıroğlu, G., Pisirici, P., & Feyzioğlu, Ö. (2024). The effect of different subtalar joint pronation amounts on postural stability, function and lower extremity alignment in healthy individuals. Foot (Edinb), 60, 102123.
  • Beard, D., & Refshauge, K. (2000). Effects of ACL reconstruction on proprioception and neuromuscular performance. Proprioception and neuromuscular control in joint stability. Philadelphia: Human Kinetics.
  • Bennell, K. L., Talbot, R. C., Wajswelner, H., Techovanich, W., Kelly, D. H., & Hall, A. J. (1998). Intra-rater and inter-rater reliability of a weight-bearing lunge measure of ankle dorsiflexion. Aust J Physiother, 44(3), 175-180.
  • Bobbert, M. F., Huijing, P. A., & van Ingen Schenau, G. J. (1987). Drop jumping. II. The influence of dropping height on the biomechanics of drop jumping. Med Sci Sports Exerc, 19(4), 339-346.
  • Bosco, C., Tarkka, I., & Komi, P. V. (1982). Effect of elastic energy and myoelectrical potentiation of triceps surae during stretch-shortening cycle exercise. Int J Sports Med, 3(3), 137-140.
  • Cobb, S. C., Bazett-Jones, D. M., Joshi, M. N., Earl-Boehm, J. E., & James, C. R. (2014). The relationship among foot posture, core and lower extremity muscle function, and postural stability. J Athl Train, 49(2), 173-180.
  • Cobb, S. C., Tis, L. L., Johnson, B. F., & Higbie, E. J. (2004). The effect of forefoot varus on postural stability. J Orthop Sports Phys Ther, 34(2), 79-85.
  • Cornwall, M. W., McPoil, T. G., Lebec, M., Vicenzino, B., & Wilson, J. (2008). Reliability of the modified Foot Posture Index. J Am Podiatr Med Assoc, 98(1), 7-13.
  • Cote, K. P., Brunet, M. E., Gansneder, B. M., & Shultz, S. J. (2005). Effects of Pronated and Supinated Foot Postures on Static and Dynamic Postural Stability. J Athl Train, 40(1), 41-46.
  • David, E., Joseph, B., Mohammad, H., Joseph, M., & Elina, S. (2020). Correlation of navicular drop to vertical and broad jump measurements in young adults. J Rehab Therapy, 2, 1-5. Glatthorn, J. F., Gouge, S., Nussbaumer, S., Stauffacher, S., Impellizzeri, F. M., & Maffiuletti, N. A. (2011). Validity and reliability of Optojump photoelectric cells for estimating vertical jump height. J Strength Cond Res, 25(2), 556-560.
  • Goldie, P. A., Bach, T. M., & Evans, O. M. (1989). Force platform measures for evaluating postural control: reliability and validity. Arch Phys Med Rehabil, 70(7), 510-517.
  • Hertel, J., Gay, M. R., & Denegar, C. R. (2002). Differences in postural control during single-leg stance among healthy individuals with different foot types. J Athl Train, 37(2), 129-132.
  • Hoch, M. C., & McKeon, P. O. (2011). Normative range of weight-bearing lunge test performance asymmetry in healthy adults. Man Ther, 16(5), 516-519.
  • Hsieh, R. L., Peng, H. L., & Lee, W. C. (2018). Short-term effects of customized arch support insoles on symptomatic flexible flatfoot in children: A randomized controlled trial. Medicine (Baltimore), 97(20), e10655.
  • Hyong, I. H., & Kang, J. H. (2016). Comparison of dynamic balance ability in healthy university students according to foot shape. J Phys Ther Sci, 28(2), 661-664.
  • Jung, D. Y., Koh, E. K., Kwon, O. Y., Yi, C. H., Oh, J. S., & Weon, J. H. (2009). Effect of medial arch support on displacement of the myotendinous junction of the gastrocnemius during standing wall stretching. J Orthop Sports Phys Ther, 39(12), 867-874.
  • Ker, R. F., Bennett, M. B., Bibby, S. R., Kester, R. C., & Alexander, R. M. (1987). The spring in the arch of the human foot. Nature, 325(7000), 147-149.
  • Kim, J. A., Lim, O. B., & Yi, C. H. (2015). Difference in static and dynamic stability between flexible flatfeet and neutral feet. Gait Posture, 41(2), 546-550. Kısacık, P., Tunay, V. B., Bek, N., Atay, Ö. A., Selfe, J., & Karaduman, A. A. (2021). Short foot exercises have additional effects on knee pain, foot biomechanics, and lower extremity muscle strength in patients with patellofemoral pain. J Back Musculoskelet Rehabil, 34(6), 1093-1104. Koura, G. M., Elimy, D. A., Hamada, H. A., Fawaz, H. E., Elgendy, M. H., & Saab, I. M. (2017). Impact of foot pronation on postural stability: An observational study. J Back Musculoskelet Rehabil, 30(6), 1327-1332.
  • Kurtoğlu, A., Çar, B., Eken, Ö., Demir, G., Türkmen, M., Setiawan, E., Alotaibi, M. H., & Elkholi, S. M. (2024). Pes planus level affects counter movement jump performance: A study on amateur male and female volleyball players. Medicine, 103(25), e38683.
  • Letafatkar A, Zandi S, Khodayi M, Vashmesara J.B. (2013). Flat foot deformity, Q angle and knee pain are interrelated in wrestlers. J Nov Physiother, 3(2), 1000138.
  • Mohammadi, H. K., Mehravar, M., Kalantari, K. K., Naimi, S. S., Baghban, A. A., Okhovatian, F., Rezasoltani, A., Mohseni Bandpei, M. A., & Taheri, N. (2018). A comparison of foot kinetic parameters between pronated and normal foot structures during forward jump landing. J Bodyw Mov Ther, 22(3), 661-665.
  • Neal, B. S., Griffiths, I. B., Dowling, G. J., Murley, G. S., Munteanu, S. E., Franettovich Smith, M. M., Collins, N. J., & Barton, C. J. (2014). Foot posture as a risk factor for lower limb overuse injury: a systematic review and meta-analysis. J Foot Ankle Res, 7(1), 55.
  • Nguyen, A. D., & Shultz, S. J. (2007). Sex differences in clinical measures of lower extremity alignment. J Orthop Sports Phys Ther, 37(7), 389-398.
  • Nilstad, A., Andersen, T. E., Bahr, R., Holme, I., & Steffen, K. (2014). Risk factors for lower extremity injuries in elite female soccer players. Am J Sports Med, 42(4), 940-948.
  • Padua, D. A., Marshall, S. W., Boling, M. C., Thigpen, C. A., Garrett, W. E., Jr, & Beutler, A. I. (2009). The Landing Error Scoring System (LESS) is a valid and reliable clinical assessment tool of jump-landing biomechanics: The JUMP-ACL study. Am J Sports Med, 37(10), 1996-2002.
  • Pişirici, P., Ekiz, M. B., & İlhan, C. A. (2020). Investigation of the acute effect of myofascial release techniques and dynamic stretch on vertical jump performance in recreationally active individuals. Journal of Physical Education and Sport, 20(3), 1569-1579.
  • Raghav, U., Mahajan, R., & Khan, F. A. (2024). Correlation of over-pronated feet with static and dynamic balance among runners. Yugato, 76(1).
  • Ramani Hardik, A., Shukla, Y. U., & Gill, M. A. Correlation of pronated foot posture and vertical jump measurement in adolescent recreational basketball players-An observational study. International Journal of Science and Healthcare Research, 9(3), 6-12.
  • Rath, M. E., Stearne, D. J., Walker, C. R., & Cox, J. C. (2016). Effect of foot type on knee valgus, ground reaction force, and hip muscle activation in female soccer players. J Sports Med Phys Fitness, 56(5), 546-553.
  • Ribeiro, A. P., Trombini-Souza, F., Tessutti, V., Rodrigues Lima, F., Sacco, I. deC., & João, S. M. (2011). Rearfoot alignment and medial longitudinal arch configurations of runners with symptoms and histories of plantar fasciitis. Clinics (Sao Paulo, Brazil), 66(6), 1027-1033.
  • Sánchez-Ramírez, C., Aguado, X., Hormazábal-Aguayo, I., Alarcón, E., Sánchez-Ramírez, C., Aguado, X., & Alarcón, E. (2020). The relation of foot morphology to performance in three vertical jumping tasks. Int J Morphol, 38(3), 545-551.
  • Sattler, T., Sekulic, D., Hadzic, V., Uljevic, O., & Dervisevic, E. (2012). Vertical jumping tests in volleyball: reliability, validity, and playing-position specifics. J Strength Cond Res, 26(6), 1532-1538.
  • Singh, A., Sharma, M., & Mathur, G. R. (2023). Biomechanical analysis of countermovement jump performance among sports players with flatfoot and normal foot structures. Applied Biological Research, 25(1), 116-121. Tiberio D. (1988). Pathomechanics of structural foot deformities. Phys Ther, 68(12), 1840-1849.
  • Tong, J. W., & Kong, P. W. (2013). Association between foot type and lower extremity injuries: systematic literature review with meta-analysis. J Orthop Sports Phys Ther, 43(10), 700-714.
  • Tourillon, R., Six, A., Bothorel, H., & Fourchet, F. (2023). Are foot posture and morphological deformation associated with ankle plantar flexion isokinetic strength and vertical drop jump kinetics? A principal component analysis. Sports Biomech, 24, 1-15.
  • Tsai, L. C., Yu, B., Mercer, V. S., & Gross, M. T. (2006). Comparison of different structural foot types for measures of standing postural control. J Orthop Sports Phys Ther, 36(12), 942-953.
  • Wen, N., Dalbo, V. J., Burgos, B., Pyne, D. B., & Scanlan, A. T. (2018). Power testing in basketball: Current practice and future recommendations. J Strength Cond Res, 32(9), 2677-2691.
  • Yoon, K. S., & Park, S. D. (2013). The effects of ankle mobilization and active stretching on the difference of weight-bearing distribution, low back pain and flexibility in pronated-foots subjects. J Exerc Rehabil, 9(2), 292-297.
  • Zhao, X., Tsujimoto, T., Kim, B., & Tanaka, K. (2017). Association of arch height with ankle muscle strength and physical performance in adult men. Biol Sport, 34(2), 119-126.
There are 43 citations in total.

Details

Primary Language English
Subjects Biomechanics in Sports Science
Journal Section Original Research Articles
Authors

Pelin Pişirici 0000-0003-1337-4194

Özlem Feyzioğlu 0000-0002-7479-4128

Nurefşan Kaygas This is me 0009-0005-3670-4696

Yahya Süleyman Mollaibrahimoğlu This is me 0009-0001-3256-7760

Publication Date September 30, 2024
Submission Date August 18, 2024
Acceptance Date September 24, 2024
Published in Issue Year 2024

Cite

APA Pişirici, P., Feyzioğlu, Ö., Kaygas, N., Mollaibrahimoğlu, Y. S. (2024). Subtalar joint pronation: Which is the real concern-presence or severity? A cross-sectional study. Turkish Journal of Kinesiology, 10(3), 169-177. https://doi.org/10.31459/turkjkin.1535023

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