Acute Effects of Copenhagen Adduction Exercise on the Stiffness and Soreness of the Hip Adductors: A Randomised Controlled Trial with Reliability Assessments

Gokhan Yagiz; Sena Adanir; Esedullah Akaras; Canan Aldırmaz; Julian Owen

doi:10.53434/gbesbd.1835774

Acute Effects of Copenhagen Adduction Exercise on the Stiffness and Soreness of the Hip Adductors: A Randomised Controlled Trial with Reliability Assessments

Abstract

Groin injuries often happen in sports involving quick direction changes, kicking, and rapid movements, with the adductor longus frequently being affected. The Copenhagen Adduction Exercise (CAE) is commonly used to help prevent such injuries. This randomised controlled trial examined the immediate effects of a single CAE session on hip adductor stiffness and perceived muscle soreness in physically active adults, following the CONSORT 2025 guidelines. Twenty-six participants (16 females, 10 males) were randomly assigned to either a CAE group, performing three sets of ten repetitions, or a control group that did not exercise. Stiffness of the adductor longus and adductor magnus was measured with the MyotonPro device before and after the intervention, along with a 0-100-point soreness scale. Intra-rater test-retest reliability for stiffness measurements was high to excellent for both muscles (ICC ≥ 0.93). The CAE group showed a significantly greater increase in adductor longus stiffness (p=0.002) and soreness (p<0.001) compared to the control, while there was no significant difference for adductor magnus stiffness (p=0.162). Changes in adductor longus stiffness were moderately positively correlated with perceived soreness (R=0.543, R²=0.295, p=0.004), but no such relationship was observed for adductor magnus. These results indicate that CAE elicits a specific, short-term mechanical and perceptual response mainly in the adductor longus. Although these reactions likely reflect normal eccentric loading rather than injury, further long-term studies are needed to determine whether repeated CAE enhances adaptations related to groin injury prevention.

Keywords

Ethical Statement

The study was reviewed and approved by the Erzurum Technical University Research and Publication Ethics Committee obtained on 16 October 2025 with approval number 2025-ETÜ-0011.

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Details

Primary Language

English

Subjects

Sports Medicine , Clinical Sciences (Other)

Journal Section

Research Article

Authors

Gokhan Yagiz ^*
0000-0002-9214-1948
Türkiye

Sena Adanir
0009-0008-0470-2989
Türkiye

Esedullah Akaras
0000-0002-0305-4632
Türkiye

Canan Aldırmaz
0000-0001-8145-6066
Türkiye

Julian Owen
0000-0002-9609-8422
United Kingdom

Publication Date

March 30, 2026

Submission Date

December 4, 2025

Acceptance Date

March 29, 2026

Published in Issue

Year 2026 Volume: 31 Number: 1

DOI

https://doi.org/10.53434/gbesbd.1835774

IZ

https://izlik.org/JA33UY39MM

Cite

RIS / Bibtex

APA

Yagiz, G., Adanir, S., Akaras, E., Aldırmaz, C., & Owen, J. (2026). Acute Effects of Copenhagen Adduction Exercise on the Stiffness and Soreness of the Hip Adductors: A Randomised Controlled Trial with Reliability Assessments. Gazi Journal of Physical Education and Sport Sciences, 31(1), 39-48. https://doi.org/10.53434/gbesbd.1835774