(1) Background: the research purpose is to identify and describe the stress and working capacity dynamics of oil and gas fly-in-fly-out (FIFO) workers in the Arctic during the fly-in period using biochemical, psychophysiological and psychological methods with further analysis of the relationship between them using objective, subjective and projective indicators. (2) Methods: The research involved 70 oil and gas FIFO specialists in the Arctic. The study of stress and working capacity was carried out using biochemical (saliva analysis for cortisol), psychophysiological (complex visual-motor reaction and variational cardiointervalometry) and psychological (questionnaire "Well-being. Activity. Mood", M. Luscher's color test and the subjective control level methods. (3) Results: There is a similarity in the dynamic curves of oil and gas FIFO employees' stress and working objective, subjective and projective indicators during the fly-in period. The maximum relationships number was obtained between objective cortisol indicators in saliva (stress), complex visual-motor response indicators (operator working capacity), variational cardiointervalometry (functionality level), and interpretation coefficients (working capacity, stress, vegetative balance) according to M. Luscher's test. (4) Conclusions: The obtained results made it possible to explain the mechanisms underlying the previously developed FIFO workers' adaptation strategies classification, in which emergency and economic adaptation strategies were identified.
Keywords: cortisol; fly-in-fly-out work; industrial psychology; job stress; objective; oil and gas extraction industry; subjective (perceived) and projective stress parameters; working capacity.