Phase 4
Completed N=12
The Influence of Menthol Gel During Exercise With Heat
Acute Exercise · Heat Exposure
Source: ClinicalTrials.gov NCT05302804 ↗
Enrolled (actual)
12
Serious AEs
0.0%
Results posted
Apr 2024
Primary outcomePrimary: Skin Blood Flow — 131.6; 119.2 arbitrary units — p=0.742
◆ Published Evidence
No publication linked
No peer-reviewed publication reporting this trial's results has been linked yet. This can indicate results are unpublished — a known publication-bias signal. We re-check periodically.
Summary
The purpose of this study is to examine the human thermoregulatory impact of applying a commercially available menthol gel (BioFreeze) to the skin prior to moderate intensity walking under heated conditions. Experimental Visits will consist of 30 min of treadmill walking at a moderate pace (3.5 mph, 5% grade) under hot conditions (38°C, 60%RH) and will be randomized and counterbalanced for BioFreeze or a hypoallergenic gel (control) application. Gels will be applied to areas commonly exposed during outdoor activity in warm conditions (shoulder to wrist, mid thigh to ankle). Accordingly, participants will wear shorts and a tank top shirt during exercise. Core temperature, skin temperature, galvanic skin response, laser doppler blood flow, and heart rate will be continuously recorded throughout the exercise bout via an integrated analog to digital converter. Sweat will be collected during exercise using commercially available absorbent patches. Thermal sensation will be assessed throughout exercise via the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) thermal sensation likert scale (cold to hot). Lastly, nude body weight will be recorded pre and post exercise for sweat rate determination. The BioFreeze and control trials will be separated by a 7-14 day washout period.
Outcome Measures
| Outcome | Result | p-value |
|---|---|---|
| PRIMARY Skin Blood Flow |
196.1; 194.8 | 0.742 |
| PRIMARY Galvanic Skin Response |
1299; 1148 | 0.048 sig |
| PRIMARY Sweat Composition |
38.9; 43.9 | .104 |
| PRIMARY Sweat Rate |
1.1; 1.3 | .051 |
| PRIMARY Thermal Perception |
0.7; 1.8 | < 0.001 sig |
| PRIMARY Average Skin Temperature |
37.6; 37.2 | .026 sig |
| PRIMARY Core Temperature |
38.1; 37.7 | .001 sig |
| PRIMARY Sweat Potassium Concentration |
7.1; 6.9 | >0.05 |
| SECONDARY % Body Fat |
20.1 | — |
| SECONDARY Skin Surface Area |
1.98 | — |
Eligibility Criteria
Inclusion Criteria
- 19-45 years of age
- cleared for physical activity via the 2022 physical activity readiness questionnaire (PARQ)
- no self-reported adverse reactions to menthol based gels
Exclusion Criteria
- outside 19-45 years of age
- not cleared for physical activity via the 2022 physical activity readiness questionnaire (PARQ)
- self-report or signs of sensitivity to menthol gels
- pregnant
- breast feeding
Data sourced from ClinicalTrials.gov (NCT05302804). Outcome figures and adverse-event rates are extracted automatically from the registry's posted results and are provided for clinician reference, not as a substitute for the primary publication. Informational only — not medical advice.