The Effect of Water Temperature on Heart Rate Variability and Cognition
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: water.
- Who it may be relevant to
- Registry conditions: Mental Acuity. Basic parameters: 18 years — 30 years · Female.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- Center list to be confirmed — check the primary protocol.
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Official title
Effects of Water Temperature on Heart Rate Variability During Cognitive Testing in Healthy Adult Women: A Randomized Crossover Trial
Overview
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.
Interventions
- Other water
water temperature
Primary outcome measures
- heart rate variability [Time frame: 3 minutes]
- cognitive performance [Time frame: 3 minutes]
Secondary outcome measures (2)
- cognitive performance [Time frame: 3 minutes]
- cognitive performance [Time frame: 3 minutes]
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)
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: Yes
Study design
- Allocation
- Randomized
- Model
- Crossover
- Masking
- Open label
- Primary purpose
- Basic science
Study locations
Center list to be confirmed — check the primary protocol.
Identifiers
NCT: NCT07654270 · STUDY00024174