Hypothalamo-pituitary adrenal axis and sympatho-adrenal medullary system responses to psychological stress were not attenuated in women with elevated physical fitness levels

Abstract

It is not clear if higher levels of cardiorespiratory fitness are associated with lower hypothalamo-pituitary adrenal (HPA) axis and sympatho-adrenal medullary (SAM) system reactivity to psychological stress in women. The association between cardio-metabolic risk markers and acute physiological responses to psychological stress in women who differ in their cardiorespiratory fitness status has also not been investigated. Women with high (n = 22) and low (n = 22) levels of fitness aged 30-50 years (in the mid-follicular phase of the menstrual cycle) were subjected to a Trier Social Stress Test (TSST) at 1500 h. Plasma concentrations of cortisol, adrenaline (Adr), noradrenaline (NA), and dopamine (DA) were measured in samples collected every 7-15 min from 1400 to 1700 h. Heart rate and blood pressure were measured at the same time points. Low-fit women had elevated serum triglyceride, cholesterol/HDL ratio, fasting glucose, and HOMA-IR levels compared with high-fit women. While cortisol, Adr, NA, HR, and blood pressure all demonstrated a significant response to the TSST, the responses of these variables did not differ significantly between high- and low-fit women in response to the TSST. Dopamine reactivity was significantly higher in the low-fit women compared with high-fit women. There was also a significant negative correlation between VO2 max and DA reactivity. These findings suggest that, for low-fit women aged 30-50 years, the response of HPA axis and SAM system to a potent acute psychological stressor is not compromised compared to that in high-fit women.

Acute hydrocortisone administration reduces cardiovagal baroreflex sensitivity and heart rate variability in young men

“…; Jayasinghe et al . ), physical exercise (590 ± 81 nmol L −1 , 30 min after a maximal 6000 m rowing ergometer test) (Jurimae et al . ), surgery (e.g.…”

“…Therefore, we expect that cortisol concentration achieved was in excess of that previously reached in studies employing longer-term 7-day oral supplementation at the same 200 mg dose (Whitworth et al 2005). The latter has been commonly used as a model of cortisol induced hypertension, whereas our approach may be more akin to a model of acute stress induced surge in cortisol, as may be seen evoked by robust stressors such as mental stress (ß550 nmol L −1 ) (Traustadottir et al 2005;Jayasinghe et al 2016), physical exercise (590 ± 81 nmol L −1 , 30 min after a maximal 6000 m rowing ergometer test) (Jurimae et al 2007), surgery (e.g. >1500 nmol L −1 ) (Lamberts et al 1997) and severe illness (828-7173 nmol L −1 ) (Sandberg et al 1956).…”

Fitter Women Did Not Have Attenuated Hemodynamic Responses to Psychological Stress Compared with Age-Matched Women with Lower Levels of Fitness

“…A thorough explanation of the requirements of the fitness test was provided to all participants after the snack. This was followed by a graded VO 2 maxtest according to the methods that have been previously used by our research group [25]. After ranking women by VO 2 max score, a median split was used to allocate women evenly into a group with high VO 2 max (higher fit group; n = 17) and a group with low VO 2 max (lower fit group; n = 17) [37].…”

“…TSST = Trier Social Stress Test, B = biological samples (results from biological samples are reported elsewhere [25]).…”

“…reduction in heart rate and blood pressure responses to stress) [16–21], as well as no influence of fitness on cardiovascular responses to stress[22–24]. In a recent study conducted by our research group, we showed that increased cardiorespiratory fitness did not moderate cortisol, catecholamine or cardiovascular responses to psychological stress (Trier Social Stress Test; TSST) in 30–50 year old women who had varying levels of physical fitness[25]. However, cardiovascular parameters were only measured every 7–15 minutes so it is possible that some outcomes were not detected.…”