Effectiveness of Cooling Strategies (Neck Cooling and Menthol Mouth Rinse) on Thermo-Perceptual and Physiological Responses in Hijab-Wearing Female Futsal Players
To investigate the effect of neck cooling and menthol mouth rinse, both independently and in combination, on repeated-sprint performance, physiological responses, and perceptual indicators in hijab-wearing female futsal players under hot and dry indoor conditions.
Design
A randomized, semi-experimental, 2x2 factorial crossover trial with block randomization and placebo control.
Settings and conduct
The study will be conducted in an indoor futsal hall under controlled hot and dry environmental conditions (temperature: 34 ± 1°C, relative humidity: 20-30%) at the Islamic Azad University, Shahrekord Branch.
Participants/Inclusion and exclusion criteria
Inclusion Criteria: Female; Aged 18-30 years; Minimum 2 years regular futsal training; Consistent sports hijab use; General health confirmed by sports physician.
Exclusion Criteria: Menthol intolerance or skin irritation from cooling; Acute illness during study; Incomplete test sessions; Medications affecting cardiovascular/respiratory/thermoregulatory systems.
Intervention groups
1. Menthol Mouth Rinse (MEN): 25 mL of 0.1% L-Menthol solution, rinsed for 10 seconds and expectorated.
2. Neck Cooling (NEC): Application of a phase-change material (PCM) cooling pack (initial temperature ~2-4°C) to the neck area.
3. Combined Intervention (MEN+NEC): Simultaneous application of both menthol mouth rinse and neck cooling.
4. Control (CON): Placebo mouth rinse (non-menthol) and a non-cooling neck pack.
Effectiveness of Cooling Strategies (Neck Cooling and Menthol Mouth Rinse) on Thermo-Perceptual and Physiological Responses in Hijab-Wearing Female Futsal Players
Public title
Effectiveness of Cooling Strategies (Neck Cooling and Menthol Mouth Rinse) on Thermo-Perceptual and Physiological Responses in Hijab-Wearing Female Futsal Players
Purpose
Health service research
Inclusion/Exclusion criteria
Inclusion criteria:
Female sex
Age range of 18 to 30
Years Minimum of two years of regular futsal training experience
Consistent use of sports hijab during training and competitions
General health confirmed by a sports medicine physician
Exclusion criteria:
Intolerance to menthol mouth rinse or occurrence of skin irritation from neck cooling
Suffering from an acute illness during the research execution period
Failure to complete at least one test session
Use of medications affecting the cardiovascular, respiratory, or thermoregulatory systems
Age
From 18 years old to 30 years old
Gender
Female
Phase
N/A
Groups that have been masked
No information
Sample size
Target sample size:
20
Randomization (investigator's opinion)
Randomized
Randomization description
This study employed a randomized, counterbalanced crossover design.
To determine the order of participation in the four intervention conditions, including menthol MEN, NEC, MEN+NEC, and control, the intervention sequences were randomly and counterbalanced using a Latin-square design, ensuring that each condition was equally distributed across different time positions to minimize order and period effects. The intervention sequences were generated by an independent researcher prior to the start of the study, and allocation was concealed using sealed, opaque envelopes.
Blinding (investigator's opinion)
Not blinded
Blinding description
Placebo
Used
Assignment
Crossover
Other design features
Quasi-experimental crossover trial with repeated measures and a 2×2 factorial structure, in which each participant completes four conditions: menthol mouth rinse (MEN), neck cooling (NEC), combined (MEN+NEC), and control (CON). The order of conditions is determined by block randomization, with at least 72 hours between sessions. The protocol is conducted in an indoor futsal hall under controlled hot-dry conditions (34±1°C, 20–30% RH).
Secondary Ids
empty
Ethics committees
1
Ethics committee
Name of ethics committee
Islamic Azad University, Shahrekord Branch
Street address
No. 10, 75th Alley, Ba Honar Street, Shahrekord
City
Shahrekord
Province
Chahar-Mahal-va-Bakhtiari
Postal code
881863003
Approval date
2025-12-20, 1404/09/29
Ethics committee reference number
IR.IAU.SHK.REC.1404.321
Health conditions studied
1
Description of health condition studied
Exercise in heat condition
ICD-10 code
ICD-10 code description
Primary outcomes
1
Description
Best sprint time
Timepoint
Calculated post-protocol after data collection
Method of measurement
Calculated using a standard formula based on the sprint times recorded across the 10 repetitions
2
Description
Performance Decrement Index
Timepoint
Upon the completion of the protocol and the collection of all temporal data
Method of measurement
Statistical analysis was performed using the standardized performance decrement formula, derived from the recorded times across 10 sprint repetitions.
3
Description
Skin Temperature
Timepoint
Pre, during, and post-activity phases.
Method of measurement
Measured using skin thermistors placed on specific body sites.
4
Description
Heart Rate
Timepoint
With smartwatch-integrated sensors
Method of measurement
Longitudinal monitoring across the pre-, intra-, and post-activity phases
5
Description
Sweat Rate & Body Mass Loss
Timepoint
Body weight measured immediately before the protocol and immediately after completion.
Method of measurement
Calculated by comparing pre- and post-activity body weight (without fluid intake during the test)
6
Description
Rating of Perceived Exertion
Timepoint
After the exercise protocol.
Method of measurement
Measured using the Borg Scale (range 6–20)
7
Description
Thermal Sensation & Thermal Comfort
Timepoint
Before, during, and after the exercise protocol.
Method of measurement
Measured via standardized thermal sensation and comfort questionnaires.
Secondary outcomes
empty
Intervention groups
1
Description
First group: Menthol Mouth Rinse (MEN): Rinsing with 25 mL of 0.1% L-Menthol solution for 10 seconds and then expectorating.
Category
Other
2
Description
Second group: Neck Cooling (NEC): Application of a phase-change material (PCM) cooling pack (initial temperature approximately 2-4°C) to the neck area.
Category
Other
3
Description
Intervention group: Third Intervention (MEN+NEC): Simultaneous application of both the menthol mouth rinse and the neck cooling.
Category
Other
4
Description
Control group: Placebo mouth rinse (non-menthol solution with similar taste) and application of a non-cooling neck pack.
Category
Other
Recruitment centers
1
Recruitment center
Name of recruitment center
Islamic Azad University, Shahrekord Branch
Full name of responsible person
Akram jafari
Street address
Shahrekord, Islamic Azad University, Shahrekord Branch
City
Shahrekord
Province
Chahar-Mahal-va-Bakhtiari
Postal code
881863003
Phone
+98 38 3336 1001
Email
Jafari.akm@gmail.com
Sponsors / Funding sources
1
Sponsor
Name of organization / entity
Islamic Azad University
Full name of responsible person
Akram Jafari
Street address
No. 10, Alley 75, Bahonar Street, Shahrekord
City
Shahrekord
Province
Chahar-Mahal-va-Bakhtiari
Postal code
881863003
Phone
+98 38 3336 1001
Email
Jafari.akm@gmail.com
Grant name
Grant code / Reference number
Is the source of funding the same sponsor organization/entity?
Yes
Title of funding source
Islamic Azad University
Proportion provided by this source
100
Public or private sector
Public
Domestic or foreign origin
Domestic
Category of foreign source of funding
empty
Country of origin
Type of organization providing the funding
Academic
Person responsible for general inquiries
Contact
Name of organization / entity
Islamic Azad University
Full name of responsible person
Akram Jafari
Position
Assistant Professor
Latest degree
Ph.D.
Other areas of specialty/work
Sport Medicine
Street address
Shahrekord, Islamic Azad University, Shahrekord Branch
City
Shahrekord
Province
Chahar-Mahal-va-Bakhtiari
Postal code
881863003
Phone
+98 38 3336 1001
Email
Jafari.akm@gmail.com
Person responsible for scientific inquiries
Contact
Name of organization / entity
Islamic Azad University
Full name of responsible person
Akram Jafari
Position
Assistant Professor
Latest degree
Ph.D.
Other areas of specialty/work
Sport Medicine
Street address
No. 10, Alley 75, Bahonar Street, Shahrekord
City
Shahrekord
Province
Chahar-Mahal-va-Bakhtiari
Postal code
881863003
Phone
+98 38 3336 1001
Email
Jafari.akm@gmail.com
Person responsible for updating data
Contact
Name of organization / entity
Islamic Azad University
Full name of responsible person
Akram Jafari
Position
Assistant Professor
Latest degree
Ph.D.
Other areas of specialty/work
Sport Medicine
Street address
No. 10, Alley 75, Bahonar St., Shahrekord
City
Shahrekord
Province
Chahar-Mahal-va-Bakhtiari
Postal code
881863003
Phone
+98 38 3336 1001
Email
Jafari.akm@gmail.com
Sharing plan
Deidentified Individual Participant Data Set (IPD)
Yes - There is a plan to make this available
Study Protocol
Yes - There is a plan to make this available
Statistical Analysis Plan
Yes - There is a plan to make this available
Informed Consent Form
Yes - There is a plan to make this available
Clinical Study Report
Yes - There is a plan to make this available
Analytic Code
Yes - There is a plan to make this available
Data Dictionary
Yes - There is a plan to make this available
Title and more details about the data/document
All data without participant names
When the data will become available and for how long
6 months after publication of the article
To whom data/document is available
University students and professors
Under which criteria data/document could be used
For future research
From where data/document is obtainable
To the researchers of this study
What processes are involved for a request to access data/document