<p>Improving the effectiveness of early rehabilitation of elderly patients after hip arthroplasty remains an urgent task. The aim of the study was to evaluate the effectiveness of isometric exercises in early (2 weeks) rehabilitation of elderly patients after hip replacement using blood parameters. The randomized study included ten elderly patients in the control (<i>n</i> = 5) and experimental (<i>n</i> = 5) groups with isometric exercises and rehabilitation techniques that were performed daily from 1 to 12 days after total cement hip arthroplasty. The effectiveness of rehabilitation was assessed by the indices of muscle traumatization (myoglobin, creatine phosphokinase, aspartate aminotransferase, and lactate dehydrogenase concentrations) and systemic inflammation (erythrocyte sedimentation rate, CRP concentrations, and interleukins IL-6, IL-8, and IL-1β) in the blood of patients on the 12th day after surgery. The indices of muscle traumatization and the concentrations of C-reactive protein and leukocytes in blood, as well as the erythrocyte sedimentation rate did not reveal any significant difference between the groups of patients. The difference between the control and experimental groups in terms of restoration of interleukin IL-6, IL-8, and IL-1β concentrations in the blood to the normal range was statistically significant according to Fisher’s exact test (<i>p</i> = 0.042). In general, these results showed that additional isometric exercises provided more effective early rehabilitation of elderly patients after endoprosthesis in comparison with the standard set of exercises and that normalization of the concentration of proinflammatory interleukins, primarily IL-6 and IL-8, can be considered as an objective indicator in assessing the effectiveness of methods of early rehabilitation of elderly patients after hip arthroplasty.</p>