The Effects of Knee Angle and Audiovisual Feedback on Sagittal Plane Body Alignment in Long Sitting Postures of University Students

Jun-Seok Lee (이준석); Ba-Da Choi (최바다); Ha-Eun Ko (고하은); Jeong-Han Kim (김정한); Chae-Hee Moon (문채희); Ye-Chan Yu (유예찬); Min-Ji Kim (김민지); Seong-Yeol Lee (이성렬); Hee-Chang Seon (선희창)

doi:10.13066/kspm.2025.20.2.1

The Effects of Knee Angle and Audiovisual Feedback on Sagittal Plane Body Alignment in Long Sitting Postures of University Students

Journal of the Korean Society of Physical Medicine
Abbr : J Korean Soc Phys Med
2025, 20(2), pp.1~10
DOI : 10.13066/kspm.2025.20.2.1
Publisher : The Korean Society of Physical Medicine
Research Area : Medicine and Pharmacy > Physical Therapy > Other physical therapy
Received : January 26, 2025
Accepted : March 22, 2025
Published : May 31, 2025

Jun-Seok Lee ¹, Ba-Da Choi ¹, Ha-Eun Ko ¹, Jeong-Han Kim ¹, Chae-Hee Moon ¹, Ye-Chan Yu ¹, Min-Ji Kim ¹, Seong-Yeol Lee ¹, Hee-Chang Seon ²

¹을지대학교 물리치료학과
²강원특별자치도원주의료원

Accredited

ABSTRACT

PURPOSE: This study examined the effects of the knee angle on body alignment in the sagittal plane of university students in prolonged sitting positions. METHODS: The study participants were 16 male and 14 female university students. The test was conducted in three different positions maintained for 30 minutes per position, with the subject looking forward as in an actual class. Sitting in a height-adjustable chair without a backrest, with hip joints locked at 90° in the seated position, the test consisted of three positions: knee angle of 90°, knee angle above 90°, and knee angle below 90°. The sagittal plane body alignment was measured before and after each test. Each subject was measured by Ex-body musculoskeletal analysis. RESULTS: All three postures showed a significant increase in the lordosis angle over time (p < .05), but no significant difference between the three postures was shown (p > .05). The thoracic-tilted angle became significantly larger in the 90°-posture test (p > .05). The craniovertebral angle was unchanged over time for any of the three postures (p > .05), and there was no difference between the three postures (p > .05). CONCLUSION: Sitting with a knee angle of less than 90° had the best effect on body alignment, rather than a knee angle of 90°, which is the conventionally recognized correct posture.

KEYWORDS

Body alignment, Knee angle, Prolonged sitting position, Sagittal plane

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* References for papers published after 2025 are currently being built.

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Journal of the Korean Society of Physical Medicine 2025 KCI Impact Factor : 1.09

The Effects of Knee Angle and Audiovisual Feedback on Sagittal Plane Body Alignment in Long Sitting Postures of University Students

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* References for papers published after 2025 are currently being built.

Journal of the Korean Society of Physical Medicine 2025 KCI Impact Factor : 1.09

The Effects of Knee Angle and Audiovisual Feedback on Sagittal Plane Body Alignment in Long Sitting Postures of University Students

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