Cold Water Exposure's Effects on Physical and Mental Health

Official title

Cold-Water Immersion's Effects on Physical and Mental Health: a 4-Week Randomized Trial Comparing Cold Tub Versus Cold Shower

Overview

An interest in cold-water immersion (CWI) to elicit diverse physiological effects has been prevalent for centuries. CWI typically consists of bodily exposure to water at temperatures ranging from 5-10º C for various durations. CWI has profound cultural significance in different areas of the world, such as in Scandinavian countries, and has emerged as a popular modality for its purported health-promoting effects. Individuals on social media have repeatedly advocated for CWI as a method to improve muscular recovery, enhance sleep, and increase immune and cognitive function. Because of this, companies that specialize in cold tub production have become popularized; however, individuals who are seeking a more cost-effective option are drawn toward cold showers for their preferred method of cold exposure. Despite the scarcity of rigorous research investigating the difference in effects of cold tub versus cold shower CWI, individuals on social media promoting CWI via a shower continue to praise its comparable benefits to that of a tub. Therefore, investigations of chronic CWI (utilizing both a cold tub and a cold shower) is vital. Thus, the purpose of the proposed study is to explore the varying effects of chronic CWI on neural and cognitive function using a cold tub and a cold shower. Further, the study aims to investigate performance measures and immune measures to create a comprehensive understanding of CWI's implications on human physiology over time. The investigators hypothesize measures relating to mental performance and health will improve after 4-weeks of CWI, and there will be no difference between tub and shower immersion groups.

Interventions

• Other Cold Water Immersion (CWI) - Cold Tub Immersion (CI)
  Once thermoneutral procedures are complete, participants in the CI group will be seated in the cold tub and submerged into the water (10º C). The sternal notch of each participant will be used as the anatomical marker to mark submersion point. Participants will sit with both arms outstretched underwater with their backs not touching the sides of the tub. Participants with a shorter stature will be provided an underwater cushion to meet the submersion requirements. The 4-minute timer will begin o
• Other Cold Water Immersion (CWI) - Cold Shower (CS)
  Once thermoneutral procedures are complete, participants in the CS group will be instructed to enter the research shower area in Gunter 1610. Within the shower area, the walls of the shower will be numbered from 1 to 4, with 1 defined as facing the faucet, 2 defined as 90° to the right of side 1, 3 defined as 180° from the faucet, and 4 defined as 270° to the right or 90° C to the left from side 1. Participants will be instructed to turn 90° to the right cycling through sides 1 to 4 and then bac

Primary outcome measures

• Sustained Attention to Response Task (SART) [Time frame: Visit 1B (Week 1) and Visit 2B (Week 4)]
• Alternate Use Task (AUT) [Time frame: Visit 1B (Week 1) and Visit 2B (Week 4)]
• Piper Fatigue Scale (PFS) [Time frame: Visit 1B (Week 1) and Visit 2B (Week 4)]
• Perceived Stress Scale (PSS) [Time frame: Visit 1B (Week 1) and Visit 2B (Week 4)]
• Mindful Attention Awareness Scale (MAAS) [Time frame: Visit 1B (Week 1) and Visit 2B (Week 4)]
• Heart Rate Variability (HRV) [Time frame: Visit 1B (Week 1) and Visit 2B (Week 4)]
• Handgrip Dynamometry [Time frame: Visit 1B (Week 1) and Visit 2B (Week 4)]
• Pittsburgh Sleep Quality Index (PSQI) [Time frame: Visit 1A (Week 1) and Visit 2A (Week 4)]
• Serum Analysis - Brain-Derived Neurotrophic Factor (BDNF) [Time frame: Visit 1A (Week 1) and Visit 2A (Week 4)]
• Serum Analysis - Cortisol [Time frame: Visit 1A (Week 1) and Visit 2A (Week 4)]

Secondary outcome measures (7)

• Anthropometric Measures - Height [Time frame: Visit 1A (Week 1) and Visit 2A (Week 4)]
• Anthropometric Measures - Weight [Time frame: Visit 1A (Week 1) and Visit 2A (Week 4)]
• Anthropometric Measures - Lean Body Mass [Time frame: Visit 1A (Week 1) and Visit 2A (Week 4)]
• Anthropometric Measures - Body Fat Percentage [Time frame: Visit 1A (Week 1) and Visit 2A (Week 4)]
• Hydration [Time frame: Visit 1A (Week 1) and Visit 2A (Week 4)]
• Qualitative Assessment [Time frame: Visit 1A (Week 1) and Visit 2A (Week 4)]
• Visual Analogue Scale (VAS) of Discomfort [Time frame: Every water immersion visit (days 1-12; 3 days per week for 4 weeks)]

Eligibility criteria

Inclusion criteria

• Healthy volunteers
• Aged 18-45

Exclusion criteria

• Current holds a cold water exposure routine (≥3 sessions in the last month, consisting of ≥4 minutes per immersion)
• Currently pregnant of planning to become pregnant
• Chronic use of anti-inflammatory medication
• Prior history of chronic disease conditions: Cardiovascular Disease, Diabetes, Cancer, Raynaud's Disease, or severe/untreated anxiety or depression

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

Parallel assignment

Masking

Open label

Primary purpose

Other

Study locations

United States · 1 center

• University of Northern Colorado — Greeley

Identifiers

NCT: NCT06667193 · 2404058903

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗