Cold-water Immersion, High Heat Sauna, Combination of Cold-water Immersion and High Heat Sauna
Conditions
Keywords
Sleep quality, Sleep architecture, Thermodynamic exposure
Brief summary
This pilot study investigates the effects of cold-water immersion, traditional sauna use, and their combination on sleep architecture and psychological health in military cadets. The study uses wearable technologies including the Oura Ring to collect objective sleep and physiological data.
Detailed description
The study will enroll 45 military cadets from The Citadel Military College, randomized into three groups: Cold-Water Immersion (CWI), High Heat Sauna (HHS), and Combined (COM). Participants will undergo a 7-day baseline period followed by a 14-day intervention. Sleep architecture and psychological-affective health will be assessed using validated wearable devices and questionnaires. The study aims to identify intervention-specific improvements in sleep and psychological health.
Interventions
BEHAVIORALCold Water Immersion
Participants will complete 14 daily sessions of cold-water immersion exposure.
BEHAVIORALHigh Heat Sauna
Participants will complete 14 evening sessions in the high heat sauna
Sponsors
Medical University of South Carolina
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 30 Years
Healthy volunteers
Yes
Inclusion criteria
1\. 18 - 30 years of age 2. Enrolled military cadet at the Citadel Military College. 3. Access to a smartphone with access to appropriate app marketplace (Apple iOS 15, Android 8.0 or newer) and reliable data access. 4\. Ability to access and operate Oura Ring application.
Exclusion criteria
1. Medical contraindications to continuous wearing of the Oura Ring. 2. Current diagnosis of neurological conditions that impact vascular blood flow or the individual's ability to regulate temperature. 3. History of cardio-vascular conditions or history of poor blood circulation. 4. History of heat stroke or known sensitivity to hot/cold environments. 5. Currently taking medications that impair fluid balance, thermoregulation, blood flow, respiration, or heart rate. 6. Known dermatological disease aggravated by changes in temperature. 7. Pregnant or trying to become pregnant within the study timeframe. Urine samples will be provided by interested female cadets to ensure they are not pregnant.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Sleep Efficiency | Each night of the baseline monitoring period (7days) and intervention phase (14days) | Percentage of sleep period spent asleep measured by the Oura Ring (percentage, %) |
| Pittsburgh Sleep Quality Index | At the end of the baseline monitoring phase (Day 7), end of intervention week 1 (Day 14), and end of intervention phase (Day 28) | Self-reported sleep quality |
| Brief Mood Introspection Scale | At the end of the baseline monitoring phase (Day 7), end of intervention week 1 (Day 14), and end of intervention phase (Day 28) | Self-reported assessment of mood consisting of 16 mood adjectives. Participants rate each adjective on a 4-point likert scale (0 = definitely don't feel, 3 = definitely feel). The assessment captures 2 core dimensions of mood valence (pleasant v. unpleasant) and arousal (active v. calm). |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Total Sleep Duration | Each night of the baseline monitoring period (7days) and intervention phase (14days) | Total duration of sleep period measured by the Oura Ring (seconds, s) |
| REM Sleep Duration | Each night of the baseline monitoring period (7days) and intervention phase (14days) | Duration of sleep period spent in REM sleep measured by the Oura Ring (seconds, s) |
| Deep Sleep Duration | Each night of the baseline monitoring period (7days) and intervention phase (14days) | Duration of sleep periods spent in deep (N3) sleep (seconds, s) |
| Light Sleep Duration | Each night of the baseline monitoring period (7days) and intervention phase (14days) | Duration of sleep period spent in light (N1 or N2) sleep (seconds, s) |
| Restless Sleep Duration | Each night of the baseline monitoring period (7days) and intervention phase (14days) | Duration of sleep period with increased registered movements as measured by the Oura Ring (seconds, s) |
| Wake After Sleep Onset (WASO) Duration | Each night of the baseline monitoring period (7days) and intervention phase (14days) | Total time spent awake after falling asleep (seconds, s) |
| RMSSD | Each night of the baseline monitoring period (7days) and intervention phase (14days) | Root mean squared of temporal latency between successive heart beats throughout sleep period measured by the Oura Ring (milliseconds, ms) |
| Nighttime Skin Temperature | Each night of the baseline monitoring period (7days) and intervention phase (14days) | Skin temperature (degrees Celsius, C°) throughout sleep period measured by the Oura Ring. |
| Sleep Time Heart Rate | Each night of the baseline monitoring period (7days) and intervention phase (14days) | Average heart rate during sleep (beats per minute, bpm) |
Countries
United States
Contacts
PRINCIPAL_INVESTIGATORMark Rosenberg, MD
Medical University of South Carolina
Outcome results
None listed