Saturation of muscle and peripheral oxygen, blood pressure, and perceived exertion in individuals exposed to repetitive muscle work

Introduction: Sex-related physiological responses to repetitive load-bearing work are of interest due to the limited available evidence and their relevance to occupational health. Objectives: To investigate potential sex-related differences in selected physiological and perceptual variables during the performance of a repetitive upper-extremity task. Methods: A non-probabilistic sample of 20 young adults (10 men and 10 women) was recruited. Participants, in a standing position, performed repetitive work cycles every 2 seconds using their dominant upper limb with the elbow flexed at 90° elbow flexion, while handling loads equivalent to 10%, 20%, and 30% of their maximum voluntary isometric contraction. Local muscle oxygenation was monitored at 0, 10, and 20 minutes in the finger flexors and elbow flexors. Peripheral oxygen saturation, blood pressure, and perceived exertion were also assessed. Results: No statistically significant differences were observed in muscle oxygen saturation; however, men showed slightly higher values. A significant sex difference in perceived exertion was identified only in the elbow flexors at 10% load at 10 minutes (p = 0.029). Blood pressure values were significantly higher in men, but only at minute 20 with the 10% and 20% loads. Conclusions: Physiological responses to repetitive work showed minimal sex-related differences. Local and global adaptations were similar, with only minor variations in perceived exertion. Future research should explore sex-related variability in samples representing the average working-age population and using alternative operational models.