NCT07608913

Brief 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. 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.

Trial Health

77
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
27

participants targeted

Target at below P25 for not_applicable

Timeline
0mo left

Started May 2026

Shorter than P25 for not_applicable

Geographic Reach
1 country

1 active site

Status
recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Progress69%
May 2026Jun 2026

First Submitted

Initial submission to the registry

May 14, 2026

Completed
11 days until next milestone

Study Start

First participant enrolled

May 25, 2026

Completed
2 days until next milestone

First Posted

Study publicly available on registry

May 27, 2026

Completed
29 days until next milestone

Primary Completion

Last participant's last visit for primary outcome

June 25, 2026

Expected
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

June 25, 2026

Last Updated

May 27, 2026

Status Verified

January 1, 2026

Enrollment Period

1 month

First QC Date

May 14, 2026

Last Update Submit

May 19, 2026

Conditions

Altitude Training AdaptationCognitive FunctionCerebral HemodynamicsExercise PerformanceHydrotherapyBalneotherapyHypoxia

Keywords

Altitude SicknessCognitionCerebrovascular CirculationPhysical PerformanceHydrotherapyHot Springs

Outcome Measures

Primary Outcomes (4)

  • 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.

    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).

    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).

    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).

    Baseline, Week 2, Week 4

Secondary Outcomes (3)

  • Maximal Oxygen Uptake (VO2max)

    Baseline, Week 5

  • 1000-Meter Running Test

    Baseline, Week 3, Week4

  • Peripheral Oxygen Saturation (SpO2)

    one month.

Study Arms (3)

Natural Recovery Group

ACTIVE COMPARATOR

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.

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±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.

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 ± 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.

Behavioral: hot spring immersion group

Interventions

Control Group：Natural RecoveryBEHAVIORAL

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.

Also known as: NR
Natural Recovery Group
Hot water immersion groupBEHAVIORAL

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.

Also known as: HWI
Hot water immersion group
hot spring immersion groupBEHAVIORAL

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.

Also known as: HSI
Hot Spring Immersion Group

Eligibility Criteria

Age11 Years - 17 Years
Sexall
Healthy VolunteersYes
Age GroupsChild (0-17)

You may qualify if:

  • 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

You may not qualify if:

  • 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

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Macao Polytechnic University

Macao, China

RECRUITING

Related Publications (6)

  • 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.

    PMID: 22752345BACKGROUND

  • MacLeod 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.

    PMID: 2034749BACKGROUND

  • Ando 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.

    PMID: 23675496BACKGROUND

  • Laukkanen 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.

    PMID: 25705824BACKGROUND

  • Ohori 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.

    PMID: 21944673BACKGROUND

  • Buchheit 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.

    PMID: 24282195BACKGROUND

MeSH Terms

Conditions

HypoxiaAltitude Sickness

Condition Hierarchy (Ancestors)

Signs and Symptoms, RespiratorySigns and SymptomsPathological Conditions, Signs and SymptomsRespiration DisordersRespiratory Tract Diseases

Central Study Contacts

Ziyue Ou, PHD

CONTACT

15626121623395356506@qq.com

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
DOUBLE
Who Masked
PARTICIPANT, OUTCOMES ASSESSOR
Purpose
PREVENTION
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Principal Investigator

Study Record Dates

First Submitted

May 14, 2026

First Posted

May 27, 2026

Study Start

May 25, 2026

Primary Completion (Estimated)

June 25, 2026

Study Completion (Estimated)

June 25, 2026

Last Updated

May 27, 2026

Record last verified: 2026-01

Locations

CN(1)