The influence of hydration status on stress‐induced hemoconcentration

Abstract

This study examined the effects of hydration status on rheological and hemodynamic activity during rest, mental stress, postural stress, and combined mental/postural stress in 24 men when euhydrated and hyperhydrated. The stress tasks elicited hemoconcentration, although the effects were less pronounced during mental stress. Hyperhydration was associated with higher plasma volume throughout. All stress tasks also perturbed hemodynamic activity, irrespective of hydration status, with the exception of heart rate reactivity, which was attenuated when hyperhydrated. As expected the combined stress during euhydration was associated with an unfavorable rheological and cardiovascular profile, which may help explain the increased incidence of cardiovascular events in the morning.

Hemoconcentration and Hemostasis During Acute Stress: Interacting and Independent Effects

“…In addition, a change in plasma volume from baseline to stress had a significant, negative correlation with changes in heart rate and SBP. Similar relationships between hemoconcentration and hemodynamic measures were reported by Veldhuijzen van Zanten and associates [69][70][71]. On the other hand, Bacon and colleagues [28] found no relationship between blood pressure changes and stress-induced hemoconcentration in patients with CHD and suggested that this may be due to the likely relatively poorer endothelial function of diseased patients.…”

Dehydration does not influence cardiovascular reactivity to behavioural stress in young healthy humans

“…Only few authors addressed the influence of hydration status on cardiovascular reactivity to mental stress (Rochette & Patterson, 2005; Veldhuijzen van Zanten et al. , 2005).…”

“…It has recently been shown that mildly enhanced hydration leads to changes in blood pressure during psychological stress tests (Rochette & Patterson, 2005). A possible explanation of this finding is given by a recent study which showed that enhanced hydration may result in higher circulatory blood and plasma volume (Veldhuijzen van Zanten et al. , 2005), which in turn increases cardiac preload, stroke volume and subsequently blood pressure reactivity.…”

A Life-Style Physical Activity Intervention and the Antibody Response to Pneumococcal Vaccination in Women

“…Participants had their body fat measured using a Bioelectrical Body Composition Analyzer (Quantum X; RJL Systems, Clinton Twp, MI), as described previously (27). Height and weight were also taken to calculate body mass index (BMI).…”