NCT06908447

Brief Summary

The behavioral within-subject cross-over design study "CoVa" aims to investigate the effect of a short-term full-body cold-water immersion vs. warm-water immersion control on value-based choice, psychological well-being, and peripheral physiology.

Trial Health

77
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
40

participants targeted

Target at P25-P50 for not_applicable

Timeline
8mo left

Started Aug 2025

Geographic Reach
1 country

1 active site

Status
recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Progress52%
Aug 2025Dec 2026

First Submitted

Initial submission to the registry

March 18, 2025

Completed
16 days until next milestone

First Posted

Study publicly available on registry

April 3, 2025

Completed
5 months until next milestone

Study Start

First participant enrolled

August 28, 2025

Completed
1.3 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

December 31, 2026

Expected
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

December 31, 2026

Last Updated

April 21, 2026

Status Verified

September 1, 2025

Enrollment Period

1.3 years

First QC Date

March 18, 2025

Last Update Submit

April 17, 2026

Conditions

Keywords

Decision-MakingPsychologyStressCold-ExposureCold-Water Immersion

Outcome Measures

Primary Outcomes (23)

  • Risk propensity

    Risk propensity, i.e., the ratio between risky and non-risky choices for each monetary value as measured in the risk decision-making task in the cold-water vs warm-water condition as described in Liu et al. (2021)

    On day 1 and after 30 days

  • Behavioral range adaptation

    Participants will perform a computer-based reinforcement learning task described in Gueguen et al. (2024) to assess reward sensitivity in different monetary contexts. Behavioral range adaptation, which reflects value range-dependent, relative reward valuation, may be altered if reward processing itself is changed through a potent shift in the physiological state. To test whether reward processing is altered after cold vs warm water exposure, the extent to which range adaptation and reference-point centering occurs will be quantified using computational modeling methods.

    On day 1 and after 30 days

  • Food choice

    Participants will be provided an ad libitum restaurant-like breakfast meal during which they can order various food items (e.g., bread, yogurts, cookies) in the desired amount. The ingested food type, nutritional value, and amount will be quantified to assess food preference after cold vs warm water exposure by linking the consumed food with a standardized food database (German Nutrient Database, Bundeslebensmittelschlüssel).

    On day 1 and after 30 days

  • Heart-rate variability

    Task-based and resting-state heart-rate variability, measured with a three-point electrocardiogram (ECG)

    On day 1 and after 30 days

  • Heart rate

    Task-based and resting-state heart rate, measured with ECG

    On day 1 and after 30 days

  • Respiration rate

    Task-based and resting-state respiration rate, measured via a respiration belt

    On day 1 and after 30 days

  • Relative amplitude of the respiratory signal

    Task-based and resting-state relative respiratory amplitude, measured via a respiratory belt

    On day 1 and after 30 days

  • Event-related skin conductance responses

    Phasic electrodermal activity, measured via electrodermal activity (EDA) electrodes

    On day 1 and after 30 days

  • Tonic skin conductance

    Tonic task-based and resting-state electrodermal activity, measured with EDA electrodes

    On day 1 and after 30 days

  • Pupil dilation

    Task-based and resting-state pupil dilation, measured via eye-tracking

    On day 1 and after 30 days

  • Skin temperature

    Thermographic imaging of the face, full-body, supraclavicular, and scapular area using a thermal camera pre-, during, and post-immersion

    On day 1 and after 30 days

  • Plasma concentration of large neutral amino acids

    Large neutral amino acid (LNAA) plasma concentration will be assessed via blood sampling at 4 time points (pre-immersion to 120 min post-immersion)

    On day 1 and after 30 days

  • Plasma concentration of catecholamines

    Catecholamines via blood sampling at 4 time points (pre-immersion to 120 min post-immersion)

    On day 1 and after 30 days

  • Plasma concentration of cortisol

    Cortisol via blood sampling at 4 time points (pre-immersion to 120 min post-immersion)

    On day 1 and after 30 days

  • Identification of epigenetic markers associated with acute cold exposure

    Epigenetic markers (micro-RNA) via blood sampling at 4 time points (pre-immersion to 120 min post-immersion)

    On day 1 and after 30 days

  • Perceived control

    Psychological changes in perceived control, measured semi-continuously via self-reports throughout the experimental day. Measures range from 0% (not at all) to 100% (very much) with 100% indicating high perceived control.

    On day 1 and after 30 days

  • Perceived freedom

    Psychological changes in perceived freedom, measured semi-continuously via self-reports throughout the experimental day. Measures range from 0% (not at all) to 100% (very much) with 100% indicating high perceived freedom.

    On day 1 and after 30 days

  • Perceived stress

    Psychological changes in perceived stress, measured semi-continuously via self-reports throughout the experimental day. Measures range from 0% (not at all) to 100% (very much) with 100% indicating high perceived stress.

    On day 1 and after 30 days

  • State of flow

    Psychological changes in perceived state of flow, measured semi-continuously via self-reports throughout the experimental day. Measures range from 0% (not at all) to 100% (very much) with 100% indicating a high state of flow.

    On day 1 and after 30 days

  • Self-efficacy

    Psychological changes in self-efficacy, measured semi-continuously via self-reports throughout the experimental day. Measures range from 0% (not at all) to 100% (very much) with 100% indicating high self-efficacy.

    On day 1 and after 30 days

  • Perceived pain

    Psychological changes in perceived pain, measured semi-continuously via self-reports throughout the experimental day. Measures range from 0% (not at all) to 100% (very much) with 100% indicating high perceived pain.

    On day 1 and after 30 days

  • Emotions

    Psychological changes in emotions and their bodily origins, measured via self-reports pre- and post-immersion. Measures will be drawn on a virtual body using an adapted version of the Nummenmaa et al. (2014) emBODY tool with red color indicating increased perception and blue indicating decreased perception.

    On day 1 and after 30 days

  • Positive affect and negative affect questionnaire

    Psychological changes in affect, measured semi-continuously via the Positive Affect Negative Affect (PANAS) questionnaire to be filled out pre- and post-immersion. Measures for each item range from 1 (not at all) to 5 (very much) with 5 indicating the highest feeling perceived at the moment.

    On day 1 and after 30 days

Secondary Outcomes (8)

  • Trait autonomy questionnaire

    On day 1 and after 30 days

  • Emotion regulation questionnaire

    On day 1 and after 30 days

  • Causality orientation questionnaire

    On day 1 and after 30 days

  • Delay discounting questionnaire

    On day 1 and after 30 days

  • Interoceptive awareness questionnaire

    On day 1 and after 30 days

  • +3 more secondary outcomes

Study Arms (2)

Cold-water immersion

EXPERIMENTAL
Behavioral: Cold-water immersion

Warm-water immersion (Control)

EXPERIMENTAL
Behavioral: Warm-water immersion (Control)

Interventions

Single 10-minute acute full-body head-out single arm-out cold-water immersion at 10-16°C on the experimental day

Cold-water immersion

Single 10-minute acute full-body head-out single arm-out cold-water immersion at 30-36°C on the experimental day

Warm-water immersion (Control)

Eligibility Criteria

Age18 Years - 40 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64)

You may qualify if:

  • years of age
  • Consent to participate
  • Fluency in German
  • Physically and mentally healthy
  • BMI 18-30 kg/m2
  • Normal day-night rhythm

You may not qualify if:

  • Raynaud syndrome
  • Cold urticaria
  • High resting heart rate (\>160 beats per minute)
  • Acute infection
  • Diagnosed current or former illnesses of
  • Brain and mind
  • Heart and blood circulation
  • Gastrointestinal system
  • Endocrine system
  • Other serious past or present medical conditions
  • Wearing of medical devices (e.g., pacemaker)
  • Fear of blood, needles, or phlebotomy
  • Allergies to plasters, gels, and other medical equipment
  • Allergies to commercially available liquid meals (e.g., shakes, yfood Labs GmbH)
  • Recurrent intake of medication which affect metabolism
  • +8 more criteria

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

German Institute of Human Nutrition Potsdam-Rehbruecke

Nuthetal, Germany

RECRUITING

Related Links

MeSH Terms

Conditions

Behavior

Study Officials

  • Soyoung Q Park, Prof. Dr.

    German Institute of Human Nutrition Potsdam-Rehbruecke

    PRINCIPAL INVESTIGATOR

Central Study Contacts

Trust Centre of the Human Study Centre Recruitment Officer

CONTACT

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
NONE
Purpose
BASIC SCIENCE
Intervention Model
CROSSOVER
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Prof. Dr.

Study Record Dates

First Submitted

March 18, 2025

First Posted

April 3, 2025

Study Start

August 28, 2025

Primary Completion (Estimated)

December 31, 2026

Study Completion (Estimated)

December 31, 2026

Last Updated

April 21, 2026

Record last verified: 2025-09

Locations