Once thermoneutral procedures are complete, participants in the CS group will be instructed to enter the research shower area. 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 four 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

Participants will be encouraged to maintain their current diet and exercise across the duration of the 4 week intervention. Participants will still be subjected to the pre- and post-intervention data collection session.

Participants will be asked to complete a paper version of the 21-item Depression Anxiety and Stress Scale (DASS-21). The DASS-21 consists of 21 questions using a 0-3 Likert scale assessing the participant's subjective mental health and stress state with a "0" indicating "Did not apply to me at all" and "3" indicating "Applied to me very much or most of the time." The DASS-21 contains 3 sub scales assessing Depression, Anxiety, and Stress consisting of 7 questions for each sub scale, where a high score of 28+ indicates "Extremely Severe" levels of Depression, a high score of 20+ indicates "Extremely Severe" levels of Anxiety, and a high score of 34+ indicates "Extremely Severe" levels of Stress, while low scores of 0-9 indicates "Normal" levels of Depression, scores of 0-7 indicates "Normal" levels of Anxiety, and scores of 0-14 indicates "Normal" levels of Stress.

Isometric grip strength will be measured by a Baseline 12-0286 Electronic Smedly Hand Dynamometer (Fabrication Enterprises, White Plains, NY). To begin the test, participants will stand upright in a relaxed position; their upper extremity peak isometric grip strength will be assessed with the shoulder in 180º of flexion, elbow at full extension, and wrist and forearm in a neutral position. When prompted, participants will squeeze the device with their dominant hand, delivering a maximal effort for 3-seconds, followed by relaxation. After 30-seconds, the test will be run again. Three sets are completed for this test, and the highest value (kg) will be recorded for analysis.

Body fat percentage (BF%) will be evaluated using air displacement plethysmography using a calibrated BODPOD (COSMED USA Inc., Concord, CA). Participants will be instructed to remove their shoes, socks, jewelry, and all additional clothing other than their base layer. Participants will then be given a swim cap to wear and body composition analysis will be performed per the manufacturer's guidelines.

Participants will be asked to complete a paper version of the Immune Status Questionnaire (ISQ). The ISQ consists of 7 items rating the respondent's past year's immune status, by inquiring about the incidence of specific immune-related complaints. The ISQ helps to establish participant's perceived immune fitness based on the previous 12 months incidence of disease symptoms. The ISQ utilizes a 0-4 Likert scale to evaluate incidence of these symptoms where a 0 indicates "Never" and a 4 indicates "Always (Almost)." The raw scores are added and converted into a final score where a final score of 0 indicates "very poor perceived immune status," while a final score of 10 indicates "excellent perceived immune status." Final scores less than 6 will be classified as reduced perceived immune function.

Participants will be asked to complete a qualitative questionnaire to indicate their perceptions of cold water therapy before and after the study. The purpose of this assessment is to see if participants' perceptions changed throughout the study. Further, this questionnaire allows participants to provide any extra qualitative feedback to gain a comprehensive insight on their chronic CWI experience. No scale is used in this survey; however, participants are given the opportunity to report their perceptions of cold immersion using the following choices: increases energy, reduces anxiety, improves sleep, improves mental health, improves physical health, improves immune system, reduces soreness or pain, or other [text response].

Participants will be asked to complete an online version of the Gastrointestinal Symptoms Questionnaire (GSQ). The GSQ is a 29-question self-reported gastrointestinal (GI) screening tool broken up into two subcategories for scoring, one for their GI symptoms experienced today and the other for their GI symptoms experienced in the last 4 weeks. There are also two open-ended question at the end of the survey, one describing any other GI symptoms not addressed in the questionnaire and another addressing normal food consumption. The GSQ will be completed online during Visits 1A and 2A.

During each session of cold therapy, participants will be assessed on their subjective ratings of discomfort as they acclimate to the cold exposure. During (at 1-minute mark) cold-water immersion, participants will be presented with the Visual Analogue Scale (VAS) of Discomfort, a modified version of a 0-10 item pain scale. This version of the VAS is a subjective measure of discomfort using a 11-point Likert scale ranging from 0 - 10 with 0 indicating "No Discomfort" and 10 indicating "Maximal Discomfort."