Date of Award
5-1-2004
Document Type
Thesis
Degree Name
M.S.E.S. in Exercise Science
Department
Health, Exercise Science, and Recreation Management
First Advisor
Edmund O. Acevedo
Second Advisor
Jeffrey S. Hallam
Third Advisor
Andrew G. Jameson
Relational Format
Dissertation/Thesis
Abstract
Certain professions involve duties that are physically and psychologically stressful. Physical stress alone and psychological stress alone are associated with increases in cardiorespiratory and stress hormone levels. Elevations in stress hormones, catecholamines and cortisol, are related to changes in blood lymphocyte populations. In particular, elevations in cortisol are related to reductions in helper T cells, helper T cell to cytotoxic T cell ratio, and natural killer cells. While numerous studies have investigated effects of physical and psychological stress alone, the effects of psychological stress during exercise has not been investigated. The purpose of this study was to describe catecholamine and cortisol responses to psychological stress during moderate exercise (60% VO2max) and determine their relationships to helper T (HT) cells, cytotoxic T (CT) cells, T cell ratio, and natural killer (NK) cells. Eight healthy subjects of average fitness between the ages of 18 and 35 were recruited to participate in the study. Each subject participated in 3 testing session including: 1) VO2max test with psychological stress familiarization, 2) cycling at 60% VO2max without the psychological stressor (NSC), and 3) cycling at 60% VO2max with the psychological stressor (SC). The psychological stressor consisted of 20 minutes of the Stroop Color Word Task (SCWT) and mental arithmetic, rotating every 2 minutes. Cardiorespiratory measurements were recorded at 10, 20, 32, and 37 minutes. Catecholamine and cortisol measurements were examined at -25, -10, 10, 32, 37, +15, +30, +45, and +60 minutes. HT cells, CT cells, T cell ratio, and NK cell measurements were examined at -25, 37, +60, and +120 minutes. The SC elicited greater elevations in heart rate (HR), respiratory rate (RR), ventilation (VE), norepinephrine (NE), and cortisol. Elevations of total cortisol were related to decreases in NK cells at 60 minutes post exercise in the SC. In conclusion, these results suggest that increased cortisol from psychological stress during exercise is related to reductions in NK cells 60 minutes post exercise. Therefore, individuals who have professions involving physical and psychological stress may have an increased risk of developing certain illnesses.
Recommended Citation
Weldy, Michael, "Psychological stress during exercise : stress hormone responses and immune function" (2004). Electronic Theses and Dissertations. 3493.
https://egrove.olemiss.edu/etd/3493