The Effect of Water Temperature on Heart Rate Variability... | NCT07654270

Studies
The Effect of Water Temperature on Heart Rate Variability and Cognition

NCT07654270

Sponsor

Arizona State University

Status

Not yet recruiting

Last Update Posted

Jun 17, 2026Actual

Enrollment

30Estimated

Phase

Not Applicable

Conditions

Mental Acuity

Interventions

water

Countries

Not provided

Protocol Section

Identification Module Status Module Sponsor/Collaborators Module Oversight Module Description Module Conditions Module Design Module Arms/Interventions Module Outcomes Module Eligibility Module Contacts/Locations Module References Module IPD Sharing Statement Module

Results Section

Participant Flow Module Baseline Characteristics Module Outcome Measures Module Adverse Events Module More Info Module

Annotation Section

Annotation Module

Document Section

Large Document Module

Derived Section

Miscellaneous Info Module Condition Browse Module Intervention Browse Module

Protocol Section

Identification Module

NCT ID

Results Section

No data available

No data is available for this block.

Annotation Section

No data available

No data is available for this block.

Document Section

No data available

No data is available for this block.

Derived Section

Miscellaneous Info Module

Version Holder

Status Module

Record Verification Date

Jun 2026

Overall Recruitment Status or Expanded Access Status

Not yet recruiting

Last Known Status

Not provided

Delayed Posting

Not provided

Why Stopped

Not provided

Expanded Access Info

Start Date

Jul 13, 2026Estimated

Primary Completion Date

Dec 15, 2026Estimated

Completion Date

Jun 15, 2027Estimated

First Submitted Date

Jun 10, 2026

First Submission Date that Met QC Criteria

Jun 12, 2026

First Posted Date

Jun 17, 2026Actual

Results Waived

Not provided

Results First Submitted Date

Not provided

Results First Submitted that Met QC Criteria

Not provided

Results First Posted Date

Not provided

Certification/Extension (aka Delayed Results) First Submitted Date

Not provided

Certification/Extension First Submitted that Passed QC Review

Not provided

Certification/Extension First Posted Date

Not provided

Last Update Submitted Date

Jun 12, 2026

Last Update Posted Date

Jun 17, 2026Actual

Sponsor/Collaborators Module

Responsible Party, by Official Title

Carol Johnston, Professor and Senior Associate Dean, Arizona State UniversityPrincipal Investigator

Lead Sponsor

Arizona State UniversityOTHER

Collaborators

Not provided

Oversight Module

Has Data Monitoring Committee (DMC)

Is FDA Regulated Drug

Is FDA Regulated Device

Is Unapproved Device

Not provided

Pediatric Postmarket Surveillance of a Device Product

Not provided

Product Exported from US

Not provided

FDAAA801 Violation

Not provided

Description Module

Brief Summary

Heart rate variability (HRV) is a key indicator of fitness, and stress resilience. Previous research has shown that HRV decreases under mental workload, including during tasks that require strict attention. Studies also show that temperature exposure affects attention: cold increases the stress response while warm water has a calming effect. Very few studies combine thermal exposure with cognitive testing, and no controlled trials have investigated whether water temperature modulates HRV responses specifically during cognitive demand.

Detailed Description

Heart rate variability (HRV) is a widely recognized physiological marker that reflects the dynamic interaction between the cardiovascular and autonomic nervous systems. HRV represents millisecond-level fluctuations in time between consecutive heartbeats. It is a key indicator of autonomic nervous system balance, with higher values indicate better recovery, fitness, and stress resilience. Previous research has shown that HRV decreases under mental workload, including during tasks that require attention, inhibition, or executive function.1-3 Studies also show that temperature exposure affects autonomic regulation: cold increases sympathetic drive, while warm water supports parasympathetic activation.4-6 Very few studies combine thermal exposure with cognitive testing, and no controlled trials have investigated whether water temperature modulates HRV responses specifically during cognitive demand.

Design Module

Study Type

Interventional

Number of References to an Expanded Access Study

Not provided

Expanded Access Types

Not provided

Patient Registry

Not provided

Target Follow-Up Duration

Not provided

Phases

Not Applicable

Interventional Study Design

Allocation

Biospecimen

No data available

No data is available for this block.

Enrollment

30Estimated

Arms/Interventions Module

Arm Groups

Label	Type	Description	Intervention Names
Warm water	Experimental	Water will be heated to ~55º C (131 ºF)	Other: water
Cold water	Placebo Comparator	Cold water: 4-6º C (41ºF)	Other: water

Interventions

Name	Type	Description	Arm Group Labels	Other Names
water	Other	water temperature	Cold water Warm water

Outcomes Module

Primary Outcomes

Measure	Description	Time Frame
heart rate variability	the measure of the variation in time between consecutive heartbeats	3 minutes
cognitive performance	Trail making test that measures cognitive flexibility, visual attention, and executive function, with interpretation based on completion times (in seconds)	3 minutes

Secondary Outcomes

Measure	Description	Time Frame
cognitive performance	Stroop Color-Word Test which measures attention span, reaction time, and ability to resist distractions	3 minutes
cognitive performance	reaction time: measured by the elapsed time between stimulus onset and an individual's response

Other Outcomes

Not provided

Eligibility Module

Eligibility Criteria

Inclusion Criteria:

Healthy women free of chronic disease (by self-report)
18-30 years of age

Exclusion Criteria:

medication/drug use that has not been consistent for the previous 3 months or will be discontinued during the trial
any acute illness
regular use of cigarettes or marijuana
pregnant or lactating women
not fluent in English
not willing to attend two in-person lab visits in downtown Phoenix and follow study protocol (including abstaining from caffeine in the 12 hours prior to testing)
not currently competing in sports or unusually high-intensity exercise protocols (e.g., high-intensity exercise greater than 30 minutes most days of the week)

Accepts Healthy Volunteers

Yes

Sex

Female

Sex/Gender Based

Yes

Sex/Gender Description

female

Minimum Age

18 Years

Maximum Age

30 Years

Standard Ages

Adult

Study Population

Not provided

Sampling Method

Not provided

Contacts/Locations Module

Central Contacts

Name	Role	Phone	Extension	Email
Carol Johnston	Contact	6024963463		carol.johnston@asu.edu

Overall Officials

Name	Affiliation	Role
Carol Johnston	Arizona State University	Principal Investigator

Locations

Not provided

IPD Sharing Statement Module

Plan to Share IPD

Description

Not provided

Types

Not provided

Time Frame

Not provided

Access Criteria

Not provided

URL

Not provided

Intervention Browse Module

MeSH Terms

ID	Term
D014867	Water

Ancestor Terms

ID	Term
D006878	Hydroxides
D000468	Alkalies
D007287	Inorganic Chemicals
D000838	Anions
D007477

Browse Leaves

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Browse Branches

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