An interventional study of Exercise + overdressing in Heat Acclimation and Thermotolerance, sponsored by United States Army Research Institute of Environmental Medicine. Not yet recruiting. Open to participants aged 18 Years to 45 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-11-05.
Sponsored by United States Army Research Institute of Environmental Medicine · Not applicable, Interventional, and Treatment
A randomized, crossover trial examining five days of exercise \& standardized overdressing versus exercise alone.
The purpose of this study is to determine the efficacy of five training sessions with overdressing + exercise to induce heat acclimation in individuals with standard fitness levels. Fifteen fit (capable of running 2 miles in 17-20 min), healthy adults will complete 90 minutes of exercise (including running at 6.0mph for up to 15 minutes at 0-1% grade, and walking at 3.5mph for up to 75 minutes at grades ranging from 0%-5%) on five occasions at room tempertature (\~20°C, \~50% RH, 1 mph air velocity). Participants will be randomized to begin in either the overdressing + exercise or standard PT clothing group and complete the study in a crossover manner. Heat acclimation induction will be assessed using standardized heat stress tests (HSTs) performed before and after five training sessions. After the final HST has occurred, participants will complete a minimum 4-week washout and then return to repeat the identical protocol in the opposite configuration (overdressing vs. PT clothing).
United States Army Research Institute of Environmental Medicine is the lead sponsor of 68 studies on the registry; 7 are open to participants now.
Of its 6 completed or terminated interventional studies of FDA-regulated products, 2 (33%) have results posted.
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Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Postmenopausal
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hemoglobin (Hb)
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Five days of exercise alone followed by four week washout then exercise + overdressing
Other: Exercise + overdressing
Exercise + overdressing following by four week washout and exercise alone
Other: Exercise + overdressing
Standardized exercise with multiple layers of clothing to stimulate heat loss mechanisms and elicit adaptations
Core temperature change
Change in core temperature following exercise alone and exercise + overdressing
Time frame: 7 days
Heart rate change
Change in heart rate following exercise alone and exercise + overdressing
Time frame: 7 days
Skin temperature change
Change in skin temperature following exercise alone and exercise + overdressing
Time frame: 7 days
Sweating rate change
Change in sweating rate following exercise alone and exercise + overdressing
Time frame: 7 days
No study locations are listed for this record.
Plan to share: No — Cannot share military personnel IDP and some proportion of volunteers will be US Servicemembers.
Start is estimated for Nov 2026; primary completion for Apr 2028, 17 months later.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is not yet recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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United States Army Research Institute of Environmental Medicine