Metabolism ChangesNCT07501923
The Effects of Daytime, Nighttime, and Combined Heat Exposure on Human Health
A study testing Daytime or Nighttime High-Temperature Exposure and Daytime and nighttime neutral temperature exposure in people with Metabolism Changes and Psychology Functional Behavior, run by Jian Cheng at 1 site in China.
Trial summary
Assess the acute effects of high-temperature exposure (including both daytime and nighttime conditions) on multiple physiological and psychological indicators, including cardiovascular, respiratory, neuropsychiatric, and metabolic functions, along with their potential mechanisms. Read more about this study
- Who is it for?
- Ages 18 to 30 yearsHealthy volunteers can take part
- Conditions the study is for
- Metabolism Changes, Psychology Functional Behavior, Cardiovascular System
- What is being tested?
- Daytime or Nighttime High-Temperature Exposure and Daytime and nighttime neutral temperature exposure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 35 participants
- Where
- 1 siteChina
- Study dates
- 1 Jun 2025to 31 Dec 2026
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
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 18 to 30 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- Age 18-30;
- In good health, with no history of cardiovascular disease, respiratory disease, diabetes, endocrine disorders, neurological or psychiatric conditions;
- No smoking or alcohol addiction, no history of substance abuse;
- No prior history of particular sensitivity to high-temperature environments.
Who cannot join
- Individuals who have experienced fever, colds, infectious diseases, or significant physical trauma within two weeks prior to the high-temperature test;
- Individuals currently using medications that may affect psychological, cognitive, cardiovascular, or respiratory functions;
- Pregnant women and lactating females;
- Participants shall not be scheduled to participate during menstruation;
- Individuals with a history of fainting or severe discomfort caused by high temperatures.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
China1 site, 1 recruiting
- Recruiting
Anhui Medical University
Hefei, Anhui, 230032
Jian Jian Cheng, +86 183 5603 7837, jiancheng@ahmu.edu.cn
About this study
Official title: Randomized Controlled Crossover Trial on the Effects of Daytime, Nighttime, and Combined Heat Exposure on Human Health
Assess the acute effects of high-temperature exposure (including both daytime and nighttime conditions) on multiple physiological and psychological indicators, including cardiovascular, respiratory, neuropsychiatric, and metabolic functions, along with their potential mechanisms.
Read the detailed description
This study will be conducted in Hefei, China, as a randomized controlled crossover human exposure trial involving approximately 50 healthy young adults. The primary objective is to systematically evaluate the acute effects of heat exposure-during both daytime and nighttime-on multiple physiological and psychological domains, including cardiovascular, respiratory, neurocognitive, and metabolic functions, and to explore the underlying biological mechanisms.
A randomized crossover design will be employed, comprising three exposure phases: nighttime heat exposure, daytime heat exposure, and combined day-night heat exposure. Each participant will undergo repeated exposures under different temperature conditions, with a washout period of at least three days between sessions to minimize carryover effects.
During the nighttime exposure phase, participants will be randomly assigned to one of two sequences. Group A will first be exposed to a nighttime heat condition at 30°C from 23:00 to 07:00 (8 hours, covering habitual sleep time), followed by exposure to a thermoneutral condition at 26°C after the washout period. Group B will follow the reverse sequence.
In the daytime exposure phase, participants will again be randomized in a crossover manner. Group A will first undergo exposure to a daytime heat condition at 32°C from 09:00 to 17:00 (8 hours, approximating a typical working day), followed by exposure to a 26°C thermoneutral condition after washout. Group B will receive the reverse sequence.
In the combined day-night exposure phase, a continuous heat exposure scenario will be simulated. Group A will first be exposed to both daytime heat (32°C, 09:00-17:00) and nighttime heat (30°C, 23:00-07:00), followed by a thermoneutral condition (26°C throughout the day and night) after washout. Group B will undergo the reverse order.
Throughout each exposure session, participants will remain in a resting state to minimize the confounding effects of physical activity. Health assessments will be conducted before exposure (within 1 hour prior), during exposure, and after exposure (within 2 hours post-exposure). These assessments will include, but are not limited to, ambulatory electrocardiogram (Holter) monitoring, blood pressure measurements, spirometry, cognitive function tests, psychological questionnaires, and collection of biological samples such as blood and urine. This comprehensive evaluation will enable characterization of the acute physiological responses to heat exposure and provide insights into potential mechanistic pathways.
- Conditions
- Metabolism Changes, Psychology Functional Behavior, Cardiovascular System, Respiratory System
- Being tested
- Daytime or Nighttime High-Temperature Exposure, Daytime and nighttime neutral temperature exposure
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Daytime or Nighttime High-Temperature ExposureOther
Daytime Exposure Phase:
The exposure group will be exposed to high temperature (32#) in a chamber for about 8 hours, resting during the whole periods
Nighttime Exposure Phase:
The exposure group will be exposed to high temperature (30#) in a chamber for about 8 hours, resting during the whole periods
Day-Night Combined Exposure Phase:
The exposure group will be exposed continuously to high temperatures during the day and night
Daytime and nighttime neutral temperature exposureOther
Daytime Exposure Phase:
The control group will be exposed to neutraltemperature (26#) in a chamber for about 8 hours, resting during the whole periods
Nighttime Exposure Phase:
The control group will be exposed to neutral temperature (26#) in a chamber for about 8 hours, resting during the whole periods
Day-Night Combined Exposure Phase:
The control group will be exposed continuously to neutraltemperatures during the day and night
| Study group | Role | What they receive |
|---|---|---|
| Intervention / Treatment | Other | Daytime or Nighttime High-Temperature Group Receives: Other: Daytime or Nighttime High-Temperature Exposure |
| Control | Other | Daytime or Nighttime Neutral -Temperature Group Receives: Other: Daytime and nighttime neutral temperature exposure |
What is being measured
The primary outcome is the main question the study is designed to answer.
Heart Rate Variability
Smart Band will be conducted during each exposure session. Time-domain and frequency-domain HRV indices (e.g., SDNN, RMSSD, LF, HF) will be derived to assess autonomic nervous system regulation.
Measured: Volunteers will be asked to wear smart band for 24 hours from 6:00 A.M. at the day of intervention to 6:00 A.M. at the next day.
Systolic and Diastolic Blood Pressure
Blood pressure will be measured using an automated sphygmomanometer under standardized resting conditions. Both systolic and diastolic values will be recorded.
Measured: Blood pressure will be examined before exposure and immediately (within 10 mins) after the exposure session
Forced Expiratory Volume in 1 Second
Pulmonary function will be assessed using spirometry according to standardized protocols. FEV1 will be recorded as a measure of airway function.
Measured: Lung function will be examined before exposure and half an hour after the exposure session
Forced Vital Capacity
Forced vital capacity will be measured via spirometry to evaluate lung volume and ventilatory function.
Measured: Lung function will be examined before exposure and half an hour after the exposure session
Interleukin-6
Venous blood samples will be collected and serum IL-6 concentrations will be quantified using enzyme-linked immunosorbent assay (ELISA) to assess systemic inflammatory response.
Measured: Blood will be collected 1 hour before and after the exposure session
C-reactive Protein
Serum CRP levels will be measured using high-sensitivity assays as a marker of systemic inflammation.
Measured: Blood will be collected 1 hour before and after the exposure session
F2-Isoprostanes
Plasma or urinary F2-isoprostanes will be quantified using validated assays as a stable biomarker of lipid peroxidation and oxidative stress.
Measured: Blood will be collected 1 hour before and after the exposure session
Superoxide Dismutase
Serum SOD activity will be measured to evaluate antioxidant defense capacity.
Measured: Blood will be collected 1 hour before and after the exposure session
Serum Creatinine
Serum creatinine will be measured using standard biochemical methods to assess renal function.
Measured: Blood will be collected 1 hour before and after the exposure session
Urinary Neutrophil Gelatinase-Associated Lipocalin
Urinary NGAL levels will be quantified using ELISA as an early biomarker of acute kidney injury.
Measured: Urine will be collected 1 hour before and after the exposure session
Profile of Mood States
Psychological status will be assessed using the validated POMS questionnaire to evaluate mood disturbances.
Measured: Scale assessments will be conducted within one hour before and after exposure.
Secondary outcomes (7)
Heart Rate
Heart rate will be continuously recorded during exposure using wearable devices.
Measured: Volunteers will be asked to wear smart band for 24 hours from 6:00 A.M. at the day of intervention to 6:00 A.M. at the next day.
Peak Expiratory Flow
PEF will be measured using a portable peak flow meter to assess expiratory function.
Measured: Lung function will be examined before exposure and half an hour after the exposure session
Tumor Necrosis Factor-alpha
Serum TNF-α levels will be measured using ELISA.
Measured: Blood will be collected 1 hour before and after the exposure session
Monocyte Chemoattractant Protein-1
Serum MCP-1 concentrations will be quantified to assess inflammatory activation.
Measured: Blood will be collected 1 hour before and after the exposure session
Glutathione
Reduced glutathione levels will be measured to assess antioxidant capacity.
Measured: Blood will be collected 1 hour before and after the exposure session
Blood Urea Nitrogen
Blood Urea Nitrogen will be measured using standard biochemical assays.
Measured: Blood will be collected 1 hour before and after the exposure session
Perceived Stress Scale
Perceived stress will be assessed using the validated Perceived Stress Scale questionnaire.
Measured: Scale assessments will be conducted within one hour before and after exposure.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted30 Mar 2026
- Study start1 Jun 2025
- Primary completion30 Sep 2026 (estimated)
- Study completion31 Dec 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Metabolism ChangesStudies 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
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Single blind
- Who is masked
- Outcomes assessor
- Enrolment
- 35 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Jian Cheng
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor-investigator, Jian Cheng, Anhui Medical University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07501923
- Sponsor's protocol ID
- 81250681
- Status last verified
- Mar 2026
- First submitted
- 18 Mar 2026
- Last updated
- 30 Mar 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 30 Mar 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Randomized Controlled Crossover Trial on the Effects of Daytime, Nighttime, and Combined Heat Exposure on Human Health
- ClinicalTrials.gov ID
- NCT07501923
- Acronym / sponsor ID
- 81250681
- Conditions
- Metabolism Changes, Psychology Functional Behavior, Cardiovascular System, Respiratory System
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 35 participants (estimated)
- Lead sponsor
- Jian ChengUniversity, hospital or other
- Study start
- 1 Jun 2025 (actual)
- Primary completion
- 30 Sep 2026 (estimated)
- Study completion
- 31 Dec 2026 (estimated)
- First posted
- 30 Mar 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Assess the acute effects of high-temperature exposure (including both daytime and nighttime conditions) on multiple physiological and psychological indicators, including cardiovascular, respiratory, neuropsychiatric, and metabolic functions, along with their potential mechanisms.
Detailed description
This study will be conducted in Hefei, China, as a randomized controlled crossover human exposure trial involving approximately 50 healthy young adults. The primary objective is to systematically evaluate the acute effects of heat exposure-during both daytime and nighttime-on multiple physiological and psychological domains, including cardiovascular, respiratory, neurocognitive, and metabolic functions, and to explore the underlying biological mechanisms.
A randomized crossover design will be employed, comprising three exposure phases: nighttime heat exposure, daytime heat exposure, and combined day-night heat exposure. Each participant will undergo repeated exposures under different temperature conditions, with a washout period of at least three days between sessions to minimize carryover effects.
During the nighttime exposure phase, participants will be randomly assigned to one of two sequences. Group A will first be exposed to a nighttime heat condition at 30°C from 23:00 to 07:00 (8 hours, covering habitual sleep time), followed by exposure to a thermoneutral condition at 26°C after the washout period. Group B will follow the reverse sequence.
In the daytime exposure phase, participants will again be randomized in a crossover manner. Group A will first undergo exposure to a daytime heat condition at 32°C from 09:00 to 17:00 (8 hours, approximating a typical working day), followed by exposure to a 26°C thermoneutral condition after washout. Group B will receive the reverse sequence.
In the combined day-night exposure phase, a continuous heat exposure scenario will be simulated. Group A will first be exposed to both daytime heat (32°C, 09:00-17:00) and nighttime heat (30°C, 23:00-07:00), followed by a thermoneutral condition (26°C throughout the day and night) after washout. Group B will undergo the reverse order.
Throughout each exposure session, participants will remain in a resting state to minimize the confounding effects of physical activity. Health assessments will be conducted before exposure (within 1 hour prior), during exposure, and after exposure (within 2 hours post-exposure). These assessments will include, but are not limited to, ambulatory electrocardiogram (Holter) monitoring, blood pressure measurements, spirometry, cognitive function tests, psychological questionnaires, and collection of biological samples such as blood and urine. This comprehensive evaluation will enable characterization of the acute physiological responses to heat exposure and provide insights into potential mechanistic pathways.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Single blind (outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Intervention / Treatment | Other | Other: Daytime or Nighttime High-Temperature ExposureDaytime or Nighttime High-Temperature Group |
| Control | Other | Other: Daytime and nighttime neutral temperature exposureDaytime or Nighttime Neutral -Temperature Group |
Who may qualify
- Ages
- 18 to 30 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (4 listed)
- Age 18-30;
- In good health, with no history of cardiovascular disease, respiratory disease, diabetes, endocrine disorders, neurological or psychiatric conditions;
- No smoking or alcohol addiction, no history of substance abuse;
- No prior history of particular sensitivity to high-temperature environments.
Key exclusion criteria (5 listed)
- Individuals who have experienced fever, colds, infectious diseases, or significant physical trauma within two weeks prior to the high-temperature test;
- Individuals currently using medications that may affect psychological, cognitive, cardiovascular, or respiratory functions;
- Pregnant women and lactating females;
- Participants shall not be scheduled to participate during menstruation;
- Individuals with a history of fainting or severe discomfort caused by high temperatures.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Daytime or Nighttime High-Temperature ExposureDaytime Exposure Phase: The exposure group will be exposed to high temperature (32#) in a chamber for about 8 hours, resting during the whole periods Nighttime Exposure Phase: The exposure group will be exposed to high temperature (30#) in a chamber for about 8 hours, resting during the whole periods Day-Night Combined Exposure Phase: The exposure group will be exposed continuously to high temperatures during the day and night | Other | Intervention / Treatment |
| Daytime and nighttime neutral temperature exposureDaytime Exposure Phase: The control group will be exposed to neutraltemperature (26#) in a chamber for about 8 hours, resting during the whole periods Nighttime Exposure Phase: The control group will be exposed to neutral temperature (26#) in a chamber for about 8 hours, resting during the whole periods Day-Night Combined Exposure Phase: The control group will be exposed continuously to neutraltemperatures during the day and night | Other | Control |
Primary outcome
Heart Rate Variability
Time frame: Volunteers will be asked to wear smart band for 24 hours from 6:00 A.M. at the day of intervention to 6:00 A.M. at the next day.
Smart Band will be conducted during each exposure session. Time-domain and frequency-domain HRV indices (e.g., SDNN, RMSSD, LF, HF) will be derived to assess autonomic nervous system regulation.
Systolic and Diastolic Blood Pressure
Time frame: Blood pressure will be examined before exposure and immediately (within 10 mins) after the exposure session
Blood pressure will be measured using an automated sphygmomanometer under standardized resting conditions. Both systolic and diastolic values will be recorded.
Forced Expiratory Volume in 1 Second
Time frame: Lung function will be examined before exposure and half an hour after the exposure session
Pulmonary function will be assessed using spirometry according to standardized protocols. FEV1 will be recorded as a measure of airway function.
Forced Vital Capacity
Time frame: Lung function will be examined before exposure and half an hour after the exposure session
Forced vital capacity will be measured via spirometry to evaluate lung volume and ventilatory function.
Interleukin-6
Time frame: Blood will be collected 1 hour before and after the exposure session
Venous blood samples will be collected and serum IL-6 concentrations will be quantified using enzyme-linked immunosorbent assay (ELISA) to assess systemic inflammatory response.
C-reactive Protein
Time frame: Blood will be collected 1 hour before and after the exposure session
Serum CRP levels will be measured using high-sensitivity assays as a marker of systemic inflammation.
F2-Isoprostanes
Time frame: Blood will be collected 1 hour before and after the exposure session
Plasma or urinary F2-isoprostanes will be quantified using validated assays as a stable biomarker of lipid peroxidation and oxidative stress.
Superoxide Dismutase
Time frame: Blood will be collected 1 hour before and after the exposure session
Serum SOD activity will be measured to evaluate antioxidant defense capacity.
Serum Creatinine
Time frame: Blood will be collected 1 hour before and after the exposure session
Serum creatinine will be measured using standard biochemical methods to assess renal function.
Urinary Neutrophil Gelatinase-Associated Lipocalin
Time frame: Urine will be collected 1 hour before and after the exposure session
Urinary NGAL levels will be quantified using ELISA as an early biomarker of acute kidney injury.
Profile of Mood States
Time frame: Scale assessments will be conducted within one hour before and after exposure.
Psychological status will be assessed using the validated POMS questionnaire to evaluate mood disturbances.
7 secondary outcomes
Heart Rate
Time frame: Volunteers will be asked to wear smart band for 24 hours from 6:00 A.M. at the day of intervention to 6:00 A.M. at the next day.
Peak Expiratory Flow
Time frame: Lung function will be examined before exposure and half an hour after the exposure session
Tumor Necrosis Factor-alpha
Time frame: Blood will be collected 1 hour before and after the exposure session
Monocyte Chemoattractant Protein-1
Time frame: Blood will be collected 1 hour before and after the exposure session
Glutathione
Time frame: Blood will be collected 1 hour before and after the exposure session
Blood Urea Nitrogen
Time frame: Blood will be collected 1 hour before and after the exposure session
Perceived Stress Scale
Time frame: Scale assessments will be conducted within one hour before and after exposure.
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 30 Mar 2026.
- Individual participant dataSharing planned: No
Related trials for Metabolism Changes
Recruiting
Metabolic Health, Bones and Nuts During Weight Loss in Adults
Weight Loss, Bone Density
Active, not recruiting
A Pilot Factorial Trial of an Integrated Lifestyle Intervention
Physical Inactivity, Overweight and Obesity
Recruiting
Change in Platelet Lipid Metabolism and Procoagulant Phenotype Induced by Cardiopulmonary Bypass. Impact on Postoperative Inflammatory Response and Bleeding Complications During Cardiac Surgery.
Cardiac Surgery, Cardiopulmonary Bypass
Recruiting
An Online Intuitive Eating Program for Pregnant Women With Obesity to Support Well-Being
Excessive Gestational Weight Gain, Pregnancy
RecruitingObservational study
Two-Year Weight Loss With GLP-1 Medications Compared With Sleeve Gastrectomy in Adults With Obesity
Obesity & Overweight
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Daytime or Nighttime High-Temperature Exposure and Daytime and nighttime neutral temperature exposure in people with Metabolism Changes and Psychology Functional Behavior, run by Jian Cheng at 1 site in China.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 30 Mar 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in China. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Jian Jian Cheng (+86 183 5603 7837, jiancheng@ahmu.edu.cn), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Heart Rate Variability (time frame: Volunteers will be asked to wear smart band for 24 hours from 6:00 A.M. at the day of intervention to 6:00 A.M. at the next day.). The study lists 11 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 30 Mar 2026.