The aim of this study was to analyze the changes in biochemical markers of oxidative stress and muscle damage, as well as psychomotor abilities during a military survival training. The study included 15 soldiers of special unit (SU), that completed 48 h military survival training combined with sleep deprivation. Before the training (P1), after 24 h (P2), and after 48 h of training (P3), blood samples were taken to measure biochemical markers. At the same time points, the measurements of divided attention and handgrip strength were conducted. Glutathione peroxidase activity decreased significantly at P3, in comparison with P1 and P2 (p < 0.0001), however, no changes were observed in other biochemical markers (i.e., lipid hydroperoxides, creatine kinase and superoxide dismutase activity) throughout the survival training (p > 0.05). The divided attention index was improved significantly at P2 and P3, as compared to P1 (p < 0.05). A tendency to change in maximum strength was found during the training period (main time effect; p = 0.08). Moreover, the strength differentiation (i.e., 50% maximum strength; 50%max) was higher at P3 than at P1 and P2 (p < 0.05). In conclusion, the 48 h survival training in the SU soldiers does not cause oxidative stress or muscle tissue damage, as well as any deterioration, and even improvement in psychomotor abilities. However, the change in strength differentiation (i.e., the production above 60%max instead of target 50%max) after the training may point to deterioration in motor control. Although it should be confirmed in further study with a more numerous group of soldiers, our findings indicate that the special unit soldiers will be able to perform, in a correct manner, specialized tasks related to their long-term activities, especially those which require divided attention. However, participation in long-term survival training, even with low workload, combined with sleep deprivation, results in a deterioration in motor control which may indicate the relevance of monitoring coordination motor abilities/skills in the training process of special unit soldiers.
Keywords: divided attention; forearm strength; lipid peroxidation; prooxidant–antioxidant homeostasis; sleep deprivation.