Cold Water Exposure's Effects on Physical and Mental Health

Summary

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.

Conditions

• Cold Exposure

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 once confirmation of the participants submersion level and posture is determined. Once completed, the participant will be instructed to slowly exit the tub and allowed to dry and change as necessary.

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 back to 1 every 15 seconds prompted by the researcher. This will allow the participant to complete three full rotations in the shower during the 4-minute intervention time. The shower faucet is modified and oriented in a way where it only produces cold water (10º C) when turned on. Once completed, the participant will be instructed to slowly exit the shower and is allowed to dry and change as necessary.

Sponsors & Collaborators

• University of Northern Colorado

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

OTHER

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

45 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2024-10-10

Primary Completion

2025-09-01

Completion

2025-10-01

Countries

• United States

Study Locations