This study will explore the physical and psychological effects of warm water immersion to the chest on student Veterans who experience symptoms of Post-Traumatic Stress Disorder (PTSD) and may also have depression, anxiety and pain.

Procedure/Protocol

Data collection will occur over 15+ consecutive weeks depending on recruitment success and scheduling availability of participants.

Day 1: After reviewing, answering questions and signing the consent form with the PI (5-20 min) , demographic information will be collected, the PCL-5 (10 min), PHQ-9 (10 min) and CES scale (5 min) will be administered by a clinical psychologist or psychiatric nurse practitioner in a private room at the SON Research Office using paper instruments.

Day 2: Data will be collected on one participant at each session at the same time of the day to control for circadian rhythms in salivary sAA, using Salimetrics protocols: 1. Collection Methods: SalivaBio Oral Swab and 2. Collecting Salivary Amylase (Appendix 11 Swab, Appendix 12 Collection). Data will be collected at the Centennial Hills YMCA and includes these activities:

Salivary Amylase

• Avoid foods with high sugar or acidity, immediately before sample collection, since they may compromise the assay by lowering saliva pH and increasing bacterial growth.
• Document consumption of alcohol, caffeine, nicotine, and prescription/over-the-counter medications within the prior 12 hours.
• Medications that specifically agonize or antagonize alpha- or beta-adrenergic processes should be avoided
• Document vigorous physical activity and the presence of oral diseases or injury.
• Consider documenting parameters to estimate saliva flow rate.
• Rinse mouth with water to remove food residue and wait at least 10 minutes after rinsing to avoid sample dilution before collecting saliva.

Protocol After arrival at the YMCA, participants will remain seated for 10 min in a quiet room adjacent to the pool area. Then pencil and paper instruments (VASA [20 sec], VASP [20 sec], MDMQ [ 7min]) will be administered and sAA collected (5min) by the PI . Next, participants will change into swimwear and enter the pool (Appendix 13 Pool Photo). A timer will be set for 15 and 45 min of immersion, with the same sequence of data collected while participants are in the water. A lifeguard will be in attendance. Following completion of the immersion intervention, participants will get dressed in the adjacent locker room and be escorted to a private room adjacent to the pool area where individual interviews will be conducted (30-60 min).

All participants are able to withdraw from the study at any time. If data has been collected on day 1 and on day 2 at baseline and 15 minutes it will be retained and analyzed.

An interview guide consisting of questions related to the intervention and participant cues will direct the conversation (Appendix 10 Interview Questions).

The interview will be initiated using a grand tour question, such as "Tell me about your experience while immersed in the water. How did you feel?" then proceed to more directed questions related to specific symptoms and specific emotional and psychological responses to the intervention (immersion). Participants may be asked to expand on specific items as applicable. At the conclusion, the participant will be asked if they have any questions or if there is anything else they would like to add. All interviews will be audio-recorded and transcribed, however, if any participants do not consent to be recorded, the researcher will take notes. Participants may conclude the interview at any time, and should they experience distress or strong emotions, the interview will be terminated. All participants will be provided with a list of available support resources.

Semi-structured interview and audio recording of the interview will be conducted in a private conference room. Only participant code numbers will be included. The audio recording on the digital recorder will never leave the investigator's presence and will be saved to the investigator's desktop on a private, pass coded protected UNLV computer, housed in a locked room. The audio recording will be immediately saved to the secure UNLV google shared drive and immediately deleted from the digital recorder and the computer desktop.

Before beginning the interview, participants will be informed that the meeting is being recorded prior to beginning the conversation. They will also be informed that the audio recording of the interview is being saved for analysis. Participants will be informed that a "code number" will be used during the interview to protect their identity.

A certified transcriptionist service Rev.com will transcribe the digitally audio recorded interview data verbatim. Rev.com has an established transcriber confidentiality agreement signed by all transcriptionists. The digitally audio recorded interview will be labeled with unique anonymous code number identifier and securely digitally delivered to the transcribing service. Transcribed transcripts will not contain personal identifying information about the participant. Once the audio recording has been converted to text, the recording residing on the secure UNLV google shared drive will be destroyed.

Inclusion Criteria:

• Self-report of previous military service, current enrollment as a student at UNLV, and current PTSD symptoms. They must be able to enter and exit the pool without assistance.

Exclusion Criteria:

• Self-report of current dental, cardiac, pulmonary or kidney disease, uncontrolled diabetes, HIV, hepatitis, mental illness (except depression), traumatic brain injury, morbid obesity, open wounds, fear of water, or missing lower extremities and presumptive or confirmed pregnancy. Pharmacologics, including antidepressants, analgesics and non-steroidal anti-inflammatories, will not be controlled for because of the difficulty of recruiting participants without comorbid depression or pain.