The Effect of Acute Mild Dehydration on Blood Pressure Control

Not Applicable

Completed

Brief Summary: The goal of this project is determine how acute mild dehydration impacts blood pressure control at rest and during static exercise. This protocol will test healthy young and older adults in a normally hydrated and dehydrated condition.

Detailed Description: The purpose of this project is determine how acute mild dehydration impacts blood pressure control at rest and during static exercise. Additionally, we will determine whether or not the sympathetic nervous system has a role in mediating blood pressure control at rest and during static exercise. This protocol will test healthy young and older adults in a normally hydrated and dehydrated condition. This will allow for a within participant comparison. Additionally, we will later determine if age alters blood pressure control at rest or during static exercise.

Recruitment & Eligibility

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Arm && Interventions

Group	Intervention	Description
Dehydration than normal hydration	Dehydration	Participants will reduce water intake over three days and abstain from any water for the final 16 hours prior to testing (visit 1). Seven to 60 days later, participants will consume water to maintain proper hydration for three days prior to testing (visit 2).
Dehydration than normal hydration	Normal hydration	Participants will reduce water intake over three days and abstain from any water for the final 16 hours prior to testing (visit 1). Seven to 60 days later, participants will consume water to maintain proper hydration for three days prior to testing (visit 2).
Normal hydration then dehydration	Dehydration	Participants will consume water to maintain proper hydration for three days prior to testing (visit 1). Seven to 60 days later, participants will reduce water intake over three days and abstain from any water for the final 16 hours prior to testing (visit 2).
Normal hydration then dehydration	Normal hydration	Participants will consume water to maintain proper hydration for three days prior to testing (visit 1). Seven to 60 days later, participants will reduce water intake over three days and abstain from any water for the final 16 hours prior to testing (visit 2).

Primary Outcome Measures

Name	Time	Method
Blood Pressure Variability	During experimental visits 1 and 2	Blood pressure variability (BPV) was calculated using standard deviation and using the average real variability index of blood pressure values. The average real variability index calculates the average of absolute differences between consecutive BP measurements and is thought to provide further prognostic value compared with traditional measures of BPV.
Blood Pressure Reactivity - Handgrip Exercise	During experimental visits 1 and 2	Change in systolic blood pressure during the second-minute handgrip exercise minus compared to pre-exercise baseline (i.e., at rest).

Secondary Outcome Measures