The effect of competition load in terms of the CK enzyme and cortisol hormone indicators related to overtraining syndrome among professional football players: an analytical study

Authors

  • Ameer Alaa Abdul-Qader College of Physical Education and Sports Sciences/ University of Baghdad, (Iraq).
  • Faris Sami Yousif Malek College of Physical Education and Sports Sciences/ University of Baghdad, (Iraq).
  • Omar Khalid Yasir College of Physical Education and Sports Sciences/ University of Baghdad, (Iraq).

DOI:

https://doi.org/10.47197/retos.v81.119545

Keywords:

Competition load, CK en-zyme, cortisol hormone, football players, non-functional overreaching (NFOR)

Abstract

Objective: The research aimed to conduct a comprehensive analysis by evaluating the system of biochemical, physical variables as multiple images to diagnose the stages of Overtraining Syndrome (OTS) for Iraqi Professional League football players for the (2023-2024) season.

Research methodology: Used a descriptive survey methodology to analyze and track the balance of adaptation mechanisms (effort exerted and adequate recovery). Physical demands were measured during matches, and athletes were measured biochemical immediately after the effort of the match, as well as after 72 hours of rest, to identify and analyze the kinetics of biochemical indicators and the sequential changes occurring throughout a full season.

Results: The hormonal system's ability to maintain its balance even when the muscular and nervous systems are under stress means that relying solely on the hormonal system may not provide a complete picture of the syndrome. In other words, the absence of obvious hormonal changes does not necessarily mean that athletes are not experiencing overtraining syndrome; it may simply indicate the body's ability to recover hormonally. The accumulation of stress causes an imbalance that first manifests in the indicators of muscular and nervous recovery mechanisms, making these indicators more sensitive in the early detection of overtraining syndrome and its stages from a hormonal perspective.

Conclusions: The research concluded that Overeffort Syndrome (OTS) is not merely a hormonal imbalance but a genuine problem in physiological adaptation mechanisms.

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Published

30-05-2026

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Section

Original Research Article

How to Cite

Abdul-Qader, A. A., Yousif Malek, F. S., & Khalid Yasir, O. (2026). The effect of competition load in terms of the CK enzyme and cortisol hormone indicators related to overtraining syndrome among professional football players: an analytical study. Retos, 80, 1622-1637. https://doi.org/10.47197/retos.v81.119545