Altitude Training AdaptationNCT07608913
Effects of Bicarbonate Spring Water Immersion on Cognitive Reliability and Post-Maximal Exercise Recovery in Adolescent Rowers During Altitude Training: A Sex-Stratified Three-Arm Randomized Controlled Trial
A study testing Hot water immersion group and hot spring immersion group in people with Altitude Training Adaptation and Cognitive Function, run by Macao Polytechnic University at 1 site in China.
Trial summary
This randomized controlled trial aims to investigate the effects of hot spring bath therapy on cognitive function recovery, cerebral hemodynamics, and athletic performance in athletes undergoing altitude training. Read more about this study
- Who is it for?
- Ages 11 to 17 yearsHealthy volunteers can take part
- Conditions the study is for
- Altitude Training Adaptation, Cognitive Function, Cerebral Hemodynamics
- What is being tested?
- Hot water immersion group and hot spring immersion group
- Type of treatment
- Lifestyle or therapy programme
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 27 participants
- Where
- 1 siteChina
- Study dates
- 25 Jan 2026to 8 Mar 2026
- Phase
- Interventional
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 11 to 17 years
- All sexes
- Healthy volunteers accepted
- Child
Who may be able to join
- Male or female aged 11-17 years- Regular endurance training (≥3 sessions/week) for ≥2 years
- No history of altitude exposure >2000m in the past 3 months
- No contraindications to hot water immersion (e.g., uncontrolled hypertension, severe cardiovascular disease, open wounds, pregnancy)
- Ability to provide written informed consent
- Willingness to abstain from other recovery modalities (e.g., massage, cryotherapy, compression garments) during the study period
- No color blindness or uncorrected visual impairment that would affect Stroop test performance
Who cannot join
- History of cardiovascular, respiratory, renal, or endocrine disorders
- Current use of medications affecting autonomic function or cognition (e.g., beta-blockers, anticholinergics, stimulants, sedatives)
- History of syncope, heat intolerance, or neurological disorders
- Acute musculoskeletal injury within the past 6 months- Regular use of sauna, hot tub, or spa within the past month- Pregnancy or breastfeeding (for female participants)
- Shift work or trans-meridian travel within 2 weeks prior to baseline assessment- Alcohol consumption >14 units/week or smoking
- History of traumatic brain injury, stroke, or psychiatric disorders
Trial locations and contacts
1 site in 1 country.
About this study
Official title: A Sex-Stratified Block-Randomized Controlled Trial of Bicarbonate-Rich Thermal Water Immersion on Cognitive Reliability and Post-Maximal Exercise Recovery in Adolescent Rowers During Field-Based Moderate-Altitude Training
This randomized controlled trial aims to investigate the effects of hot spring bath therapy on cognitive function recovery, cerebral hemodynamics, and athletic performance in athletes undergoing altitude training. Participants will be randomly assigned to either a hot spring intervention group, a hot water control group, or a blank control group. The hot spring intervention group receives hot spring baths (38°C, 20 minutes) combined with altitude training; the hot water control group receives hot water baths (38°C, 20 minutes) combined with altitude training; and the blank control group receives standard recovery procedures combined with altitude training. Primary outcome measures include cognitive performance assessments (Stroop test, psychomotor vigilance test) and cerebral hemodynamic indicators (functional near-infrared spectroscopy, transcranial Doppler ultrasound). Secondary outcomes included exercise capacity (maximal oxygen uptake, triathlon performance, 500-meter test), blood lactate, and hematological parameters (white blood cells, neutrophils, platelets). These findings may provide evidence for non-pharmacological interventions to enhance cognitive recovery and brain adaptation during altitude training.
- Conditions
- Altitude Training Adaptation, Cognitive Function, Cerebral Hemodynamics, Exercise Performance, Hydrotherapy, Balneotherapy
- Being tested
- Control Group：Natural Recovery, Hot water immersion group, hot spring immersion group
- Keywords
- Altitude Sickness, Cognition, Cerebrovascular Circulation, Physical Performance, Hydrotherapy, Hot Springs
- Medical subject headings
- Hypoxia, Altitude Sickness
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Control Group：Natural RecoveryBehavioural
Also called NR
Control group participants will undergo the same altitude training protocol (altitude 1600 meters) for 4 weeks. After each training session, participants will receive standard recovery procedures, including 20 minutes of passive rest in a thermoneutral environment (room temperature 24°C), supplemented with mild hydration and self-selected stretching. No hydrothermal intervention will be provided.
Hot water immersion groupBehavioural
Also called HWI
The hot water immersion group will undergo a 4-week altitude training at 1600 meters above sea level. Subjects will receive a 20-minute hot water immersion (daily tap water, 38°C±1°C) in a standardized indoor hot spring facility. The immersion protocol includes whole-body immersion up to the neck for 20 minutes, followed by a 10-minute rest before leaving the facility. Three times per week.
hot spring immersion groupBehavioural
Also called HSI
The hot spring immersion group will undergo a 4-week high-altitude training at an altitude of 1600 meters. Subjects will receive a 20-minute hot spring therapy (natural hot spring water, 38°C ± 1°C) in a standardized indoor hot spring facility. The immersion protocol includes whole-body immersion to the neck for 20 minutes, followed by a 10-minute rest before leaving the facility. Three times per week.
| Study group | Role | What they receive |
|---|---|---|
| Natural Recovery Group | Active comparator | Control group participants will undergo the same altitude training protocol (altitude 1600 meters) for 4 weeks. Participants underwent a 20-minute quiet seated rest at 16:00 on Tuesdays, Thursdays, and Saturdays, with ad libitum water consumption permitted and electronic devices prohibited. Receives: Behavioral: Control Group：Natural Recovery |
| Hot water immersion group | Active comparator | The hot water immersion group will undergo a 4-week altitude training at 1600 meters above sea level. Subjects will receive a 20-minute hot water immersion (daily tap water, 38°C±0.5°C) in a standardized indoor hot spring facility. The immersion protocol includes partial-body immersion up to the xiphoid process (lower chest) for 20 minutes, followed by a 10-minute rest before leaving the facility. Three times per week. Receives: Behavioral: Hot water immersion group |
| Hot Spring Immersion Group | Experimental | The hot spring immersion group will undergo a 4-week high-altitude training at an altitude of 1600 meters. Subjects will receive a 20-minute hot spring therapy (natural hot spring water, 38°C ± 0.5°C) in a standardized indoor hot spring facility. The immersion protocol includes partial-body immersion up to the xiphoid process (lower chest) for 20 minutes, performed three times per week, followed by a 10-minute rest before leaving the facility. Receives: Behavioral: hot spring immersion group |
What is being measured
The primary outcome is the main question the study is designed to answer.
Psychomotor Vigilance Test (PVT)
5-minute PVT measuring sustained attention and psychomotor vigilance. Outcome variables: mean reciprocal response time (1/RT). Administered via standardized software on a tablet/computer. Unit: second.
Measured: Baselines were measured at the formal start of the experiment, at night during the 2nd, 3rd, and 4th weeks (post-intervention) after ascending the plateau, and post-tests were conducted one week after descending the plateau.
Stroop Test Performance
Computerized Stroop Color-Word Test measuring executive function and cognitive inhibition. Outcome variables: reaction time (ms). Administered in a quiet, temperature-controlled room (22-24°C). Unit: milliseconds (ms).
Measured: Baselines were measured at the formal start of the experiment, at night during the 2nd, 3rd, and 4th weeks (post-intervention) after ascending the plateau, and post-tests were conducted one week after descending the plateau.
Cerebral Oxygenation (fNIRS)
Changes in oxygenated hemoglobin (HbO) and deoxygenated hemoglobin (HbR) in the prefrontal cortex during cognitive tasks, measured by functional near-infrared spectroscopy (fNIRS) with a multichannel system. Outcome: relative changes in HbO and HbR concentrations. Unit: micromolar (μM).
Measured: Baseline, Week 2, Week 5
Cerebral Blood Flow Velocity (TCD)
Mean blood flow velocity in the middle cerebral artery (MCA) and anterior cerebral artery (ACA) measured by transcranial Doppler ultrasound (TCD) with 2MHz probe. Measurements taken in supine position after 10 minutes of rest. Outcome: mean velocity (cm/s). Unit: centimeters/second (cm/s).
Measured: Baseline, Week 2, Week 4
Secondary outcomes (3)
Maximal Oxygen Uptake (VO2max)
Maximal oxygen uptake measured using a portable metabolic analyzer during a graded exercise test on a rowing ergometer. Test protocol: incremental ramp test to exhaustion. Unit: mL/kg/min.
Measured: Baseline, Week 5
1000-Meter Running Test
1000-meter maximal effort running test on a standard 400m track or treadmill. Total completion time recorded. Unit: seconds (s).
Measured: Baseline, Week 3, Week4
Peripheral Oxygen Saturation (SpO2)
Resting peripheral oxygen saturation measured via fingertip pulse oximeter after 10 minutes of seated rest. Unit: percentage (%).
Measured: one month.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted27 May 2026
- Study start25 Jan 2026
- Primary completion26 Feb 2026
- Study completion8 Mar 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (6)Papers the sponsor has linked to this study.
- Other trials for Altitude Training AdaptationStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind
- Who is masked
- Participant, Outcomes assessor
- Enrolment
- 27 participants (actual)
Sponsor and investigators
- Lead sponsor
- Macao Polytechnic University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Ziyue Ou, Macao Polytechnic University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07608913
- Sponsor's protocol ID
- 202502AS100005-1
- Status last verified
- Jul 2026
- First submitted
- 14 May 2026
- Last updated
- 4 Aug 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided: The current research project has not yet been completed, and the data have not been publicly released. After publication, sharing will be decided on a case-by-case basis.
Publications
Stanley J, Peake JM, Buchheit M. Consecutive days of cold water immersion: effects on cycling performance and heart rate variability. Eur J Appl Physiol. 2013 Feb;113(2):371-84. doi: 10.1007/s00421-012-2445-2. Epub 2012 Jul 3.
PubMed 22752345MacLeod CM. Half a century of research on the Stroop effect: an integrative review. Psychol Bull. 1991 Mar;109(2):163-203. doi: 10.1037/0033-2909.109.2.163. No abstract available.
PubMed 2034749Ando S, Hatamoto Y, Sudo M, Kiyonaga A, Tanaka H, Higaki Y. The effects of exercise under hypoxia on cognitive function. PLoS One. 2013 May 10;8(5):e63630. doi: 10.1371/journal.pone.0063630. Print 2013.
PubMed 23675496Laukkanen T, Khan H, Zaccardi F, Laukkanen JA. Association between sauna bathing and fatal cardiovascular and all-cause mortality events. JAMA Intern Med. 2015 Apr;175(4):542-8. doi: 10.1001/jamainternmed.2014.8187.
PubMed 25705824Ohori T, Nozawa T, Ihori H, Shida T, Sobajima M, Matsuki A, Yasumura S, Inoue H. Effect of repeated sauna treatment on exercise tolerance and endothelial function in patients with chronic heart failure. Am J Cardiol. 2012 Jan 1;109(1):100-4. doi: 10.1016/j.amjcard.2011.08.014. Epub 2011 Sep 23.
PubMed 21944673Buchheit M, Simpson BM, Garvican-Lewis LA, Hammond K, Kley M, Schmidt WF, Aughey RJ, Soria R, Sargent C, Roach GD, Claros JC, Wachsmuth N, Gore CJ, Bourdon PC. Wellness, fatigue and physical performance acclimatisation to a 2-week soccer camp at 3600 m (ISA3600). Br J Sports Med. 2013 Dec;47 Suppl 1(Suppl 1):i100-6. doi: 10.1136/bjsports-2013-092749.
PubMed 24282195