This finding led the authors to the conclusion that the changes in the androgen levels observed in other studies may be rather attributable to comorbidities in the aging population than to the aging process itself. It is widely accepted that aging per se decreases the T and fT concentrations in men (48), especially after the fifth decade of life (49), but the degree of this process also depends on the health status of the studied men (50). On the other hand, the BMI-independent relationship between androgens and AAG could be explained by the fact that extrahepatic AAG expression occurs in cell types other than the adipose tissue and may be regulated by inflammatory mediators, as in hepatocytes (41). The negative association between T concentration and the inflammatory markers, which is frequently reported (12, 43), supports this conclusion. The participants provided their written informed consent to participate in this study. The studies were conducted in accordance with the local legislation and institutional requirements. Therefore, promoting a healthy lifestyle, regular physical activity, and a balanced diet appears essential for reducing systemic inflammation. The measurement method for T and C was standardized against the isotope dilution gas chromatography–mass spectrometry (ID GC/MS) reference method. Plasma IL-6 concentration was determined by enzyme-linked immunosorbent assay (ELISA) according to the manufacturer’s instruction (R&D Systems, Inc. Minneapolis, MN, USA). All volunteers were fully informed about the aim of this study and gave written consent to take part in the investigation. Ethical approval for the experimental procedures was obtained from the Local Ethical Committee at the Regional Medical Chamber in Krakow, Poland (opinion no. 48/KBL/OIL/2009), and the study protocol was conducted in accordance with the Declaration of Helsinki. Rotter I, Ciosek Ż, Syroka A and Ryl A (2025) A cross-sectional study of testosterone deficiency and inflammatory markers in older men. Moreover, the positive correlation between testosterone and physical activity level suggests that exercise training may reduce the age-related decrease in gonadal androgens, which seems to be one of the main beneficial effects (anti-inflammatory one) of physical activity in aging men. Based on the above literature data, it may be inferred that the correlation between androgens and inflammatory markers observed in this study is not accidental. The study investigated the correlation between anthropometric factors, hormone levels, and hsCRP concentrations in patients with and without testosterone deficiency (Table 1). The relationship between anthropometric factors, and hormone levels in the group of patients with testosterone deficiency syndrome (TDS) according to hsCRP concentration. In Table 3, the relationship between anthropometric factors, and hormone levels in the group of patients with testosterone deficiency (TDS) was analyzed based on hsCRP concentration. In Table 2, the relationship between anthropometric factors, and hormone levels in the group of patients without testosterone deficiency was analyzed based on hsCRP concentration. This cross-sectional study aimed to examine the relationship between total testosterone (TT) levels, the diagnosis of testosterone deficiency syndrome (TDS), and high-sensitivity C-reactive protein (hsCRP) concentrations in aging men. The training-induced changes in the androgen concentrations, regardless of whether they are related to the direct stimulation of the HPG axis or to the effects of body fat–androgens interactions, may be of great importance because we have demonstrated that they are inversely correlated with markers of inflammation and blood lipids (Figures 1 and 2). Although we have demonstrated that physically active men tend to have higher sex hormone concentrations than do the inactive ones (see Results, Bivariate Correlations), there was a significant negative correlation between age and the androgen status, especially the fT concentration, i.e., the biologically active form of gonadal androgens (see Table 2).