Effects of Regular Exercise on Ischemia-Modified Albumin and Total Sulfhydryl Levels in Young Women: A Cross-Sectional Study

Omer Faruk Bilici^1*Muhammed Zahit Kahraman²Ali Türker³Sinan Seyhan⁴Mehmet Furkan Sahin⁵Halit Demir⁶Gorkem Acar⁷Muhammed Fatih Bilici⁸Caglar Soylu^9*Tarkan Söğüt¹⁰Abdullah Bakum¹¹

• ¹Institute of Health Sciences, Marmara University, Istanbul, Türkiye
• ²Faculty of Sports Sciences, Bitlis Eren University, Bitlis, Türkiye
• ³Recreation Management, Faculty of Applied Sciences, Karamanoğlu Mehmetbey University, Karaman, Türkiye
• ⁴Department of Coaching Education, Faculty of Sport Sciences, Manisa Celal Bayar University, Manisa, Türkiye
• ⁵Coaching Education, Faculty of Sports Sciences, Muş Alparslan University, Muş, Türkiye
• ⁶Faculty of Science, Van Yüzüncü Yıl University, Van, Türkiye
• ⁷Department of Sport Science, Institute of Graduate Education, Manisa Celal Bayar University, Manisa, Turkey, Manisa, Türkiye
• ⁸Faculty of Sports Sciences, Muş Alparslan University, Muş, Türkiye
• ⁹Gulhane Faculty of Physiotherapy and Rehabilitation, University of Health Sciences, Ankara, Türkiye
• ¹⁰Department of coaching Education and Sports, Siirt Universirty, Siirt, Türkiye
• ¹¹Faculty of Sports Sciences, Selcuk University, Konya, Türkiye

Regular physical activity exerts systemic health benefits, including improvements in redox homeostasis and antioxidant defense. Ischemia-modified albumin (IMA) and total sulfhydryl groups (–SH) are sensitive biomarkers reflecting oxidative protein modification and thiol-dependent antioxidant capacity, respectively. However, data on their relationship in young women engaged in structured exercise are limited. This cross-sectional study, recruiting participants from university campuses and local fitness facilities, investigated associations between regular exercise and serum IMA and –SH concentrations in healthy young women to provide insight into potential redox This is a provisional file, not the final typeset article differences and sex-specific physiological profiles. A design included 30 women aged 18–25 years, divided into an exercise group (n = 15), who performed structured training ≥3 sessions per week for at least one year, and a control group (n = 15) with no structured exercise history. Following ethical approval and informed consent, venous blood samples were collected after overnight fasting. Serum IMA was quantified using the albumin–cobalt binding assay, and –SH concentrations were determined by the Ellman method. All analyses were performed in duplicate under standardized conditions. Independent samples t-tests and effect sizes (Cohen's d) with 95% confidence intervals were calculated. Baseline anthropometric variables (age, height, weight) did not differ significantly between groups. Serum IMA levels were significantly higher in the exercise group compared with controls (0.75 ± 0.09 vs. 0.61 ± 0.08 ABSU; p < 0.001; d = 1.65). Conversely, –SH concentrations were significantly lower in exercising women than in sedentary peers (0.370 ± 0.046 vs. 0.447 ± 0.036 mmol/L; p < 0.001; d = -1.88). Both biomarkers demonstrated very large effect sizes, indicating robust differences in oxidative stress and antioxidant defense profiles associated with regular training. In conclusion, in this cross-sectional analysis, regular structured exercise in young women was associated with a distinct redox profile characterized by elevated IMA and reduced –SH concentrations. This dual pattern may represent differences in redox homeostasis involving potential enhanced oxidative protein modification and increased thiol utilization. IMA and –SH appear to be complementary biomarkers for assessing exercise-associated redox profiles. Future longitudinal studies are needed to confirm causality and clinical relevance.