Acquiring and Targeting Heat Exposures Necessary for Action

Acquiring and Targeting Heat Exposures Necessary for Action

Change in Rectal Temperature at Rest [ Time Frame: Through study completion, an average of 14 days ]
Rectal thermometer will be self-inserted by participants to assess core temperature prior to exercise-heat stress bouts

Change in Rectal Temperature Rate of Rise [ Time Frame: Through study completion, an average of 14 days ]
Rectal thermometer will be self-inserted by participants to assess core temperature during exercise-heat stress bouts

Change in Rectal Temperature at Thermal Threshold (38.5C) [ Time Frame: Measured throughout 5 90-minute exercise-heat stress bouts (heat acclimation sessions) ]
Rectal thermometer will be self-inserted by participants to assess core temperature during exercise-heat stress bouts at the thermal threshold of 38.5C

Change in Mean Skin Temperature [ Time Frame: Through study completion, an average of 14 days ]
Prior to start of exercise, participants will be instrumented with iButton skin temperature sensors on the chest, shoulder, abdomen, neck, back, thigh, and calf

Change in Heart Rate [ Time Frame: Through study completion, an average of 14 days ]
A heart rate monitor will be worn by participants throughout the exercise-heat stress bouts

Change in Heart Rate at Thermal Threshold (38.5C) [ Time Frame: Measured throughout 5 90-minute exercise-heat stress bouts (heat acclimation sessions) ]
A heart rate monitor will be worn by participants throughout the exercise-heat stress bouts to assess HR at the thermal threshold of 38.5C

Change in Whole Body Sweat Rate [ Time Frame: Measured at the beginning and end of 5 90-minute exercise-heat stress bouts (heat acclimation sessions) ]
Difference in body weight measurement measured prior to and at the cessation of each exercise-heat stress bout

Change in Sweat Metabolite and Protein Expression [ Time Frame: Measurement completed during each exercise-heat stress bout (Heat Tolerance Tests 1 [days 5 and 12] and 2 [days 6 and 13]) both before and immediately after heat acclimation as well as the final heat acclimation session (HA5 – day 11) ]
Sweat samples will be collected and assessed for metabolite and protein expression discovery via mass spectrometry

Change in Cognitive Measures – Visual Vigilance [ Time Frame: Measurement completed immediately after one exercise-heat stress bout (Heat Tolerance Test 2 – days 6 and 13) both before and immediately after heat acclimation ]
Participants will perform an assessment of visual vigilance through a validated computer programming system. The test is part of a larger Testing battery which should take approximately 30 minutes for completion

Change in Cognitive Measures – Psychomotor Vigilance [ Time Frame: Measurement completed immediately after one exercise-heat stress bout (Heat Tolerance Test 2 – days 6 and 13) both before and immediately after heat acclimation ]
Participants will perform an assessment of psychomotor vigilance through a validated computer programming system. The test is part of a larger Testing battery which should take approximately 30 minutes for completion

Change in Cognitive Measures – Four Choice Task [ Time Frame: Measurement completed immediately after one exercise-heat stress bout (Heat Tolerance Test 2 – days 6 and 13) both before and immediately after heat acclimation ]
Participants will perform an assessment of four choice task success through a validated computer programming system. The test is part of a larger Testing battery which should take approximately 30 minutes for completion

Change in Cognitive Measures – Match to Sample [ Time Frame: Measurement completed immediately after one exercise-heat stress bout (Heat Tolerance Test 2 – days 6 and 13) both before and immediately after heat acclimation ]
Participants will perform an assessment of match to sample success through a validated computer programming system. The test is part of a larger Testing battery which should take approximately 30 minutes for completion

Change in Cognitive Measures – Repeated Acquisition [ Time Frame: Measurement completed immediately after one exercise-heat stress bout (Heat Tolerance Test 2 – days 6 and 13) both before and immediately after heat acclimation ]
Participants will perform an assessment of repeated acquisition through a validated computer programming system. The test is part of a larger Testing battery which should take approximately 30 minutes for completion

Change in Cognitive Measures – Grammatical Reasoning [ Time Frame: Measurement completed immediately after one exercise-heat stress bout (Heat Tolerance Test 2 – days 6 and 13) both before and immediately after heat acclimation ]
Participants will perform an assessment of grammatical reasoning through a validated computer programming system. The test is part of a larger Testing battery which should take approximately 30 minutes for completion

Change in Cognitive Measures – Profile of Mood States [ Time Frame: Measurement completed immediately after one exercise-heat stress bout (Heat Tolerance Test 2 – days 6 and 13) both before and immediately after heat acclimation ]
Participants will perform an assessment of profile of mood states through a validated computer programming system. The test is part of a larger Testing battery which should take approximately 30 minutes for completion

Change in Cognitive Measures – Stroop Task [ Time Frame: Measurement completed immediately after one exercise-heat stress bout (Heat Tolerance Test 2 – days 6 and 13) both before and immediately after heat acclimation ]
Participants will perform an assessment of stroop task success through a validated computer programming system. The test is part of a larger Testing battery which should take approximately 30 minutes for completion

Change in Physical Performance – Anaerobic Performance [ Time Frame: Measurements completed immediately after the cognitive battery performed during the Heat Tolerance Test 2 (days 6 and 13) both before and immediately after heat acclimation ]
Participants will be assessed for anaerobic performance with the completion of a 400 meter sprint for time. This test is part of a larger physical performance battery test which should take approximately 30 minutes for completion

Change in Physical Performance – Agility Performance [ Time Frame: Measurements completed immediately after the cognitive battery performed during the Heat Tolerance Test 2 (days 6 and 13) both before and immediately after heat acclimation ]
Participants will be assessed for anaerobic performance with the completion of a quick feet agility test. This test is part of a larger physical performance battery test which should take approximately 30 minutes for completion

Change in Physical Performance – Upper Body Strength Performance [ Time Frame: Measurements completed immediately after the cognitive battery performed during the Heat Tolerance Test 2 (days 6 and 13) both before and immediately after heat acclimation ]
Participants will be assessed for upper body strength performance with the completion of a handgrip strength test. This test is part of a larger physical performance battery test which should take approximately 30 minutes for completion

Change in Physical Performance – Lower Body Power Performance [ Time Frame: Measurements completed immediately after the cognitive battery performed during the Heat Tolerance Test 2 (days 6 and 13) both before and immediately after heat acclimation ]
Participants will be assessed for lower body power performance with the completion of a vertical jump test. This test is part of a larger physical performance battery test which should take approximately 30 minutes for completion

Change in Physical Performance – Lower Body Kinematic Performance [ Time Frame: Measurements completed immediately after the cognitive battery performed during the Heat Tolerance Test 2 (days 6 and 13) both before and immediately after heat acclimation ]
Participants will be assessed for lower body kinematic performance with the completion of the Landing Error Scoring System (LESS) Test. This test is part of a larger physical performance battery test which should take approximately 30 minutes for completion

Change in Physical Performance – Balance Performance [ Time Frame: Measurements completed immediately after the cognitive battery performed during the Heat Tolerance Test 2 (days 6 and 13) both before and immediately after heat acclimation ]
Participants will be assessed for balance performance with the completion of the Balance Error Scoring System (BESS) Test. This test is part of a larger physical performance battery test which should take approximately 30 minutes for completion

Change in Musculoskeletal Gene and Protein Expression [ Time Frame: Measurement completed after the performance of an exercise-heat stress bout and physical performance battery (Heat Tolerance Test 2 – days 6 and 13) both before and immediately after heat acclimation ]
Musculoskeletal tissue samples will be collected for analysis via RNA-seq

Change in Musculoskeletal Fiber-Typing [ Time Frame: Measurement completed after the performance of an exercise-heat stress bout and physical performance battery (Heat Tolerance Test 2 – days 6 and 13) both before and immediately after heat acclimation ]
Musculoskeletal tissue samples will be collected for fiber-type analysis via immunohistochemical procedures

Change in Musculoskeletal Mitochondrial Function [ Time Frame: Measurement completed after the performance of an exercise-heat stress bout and physical performance battery (Heat Tolerance Test 2 – days 6 and 13) both before and immediately after heat acclimation ]
Musculoskeletal tissue samples will be collected for analysis of mitochondrial function

Change in Subcutaneous Abdominal Tissue (SCAAT) Lipolysis Rate [ Time Frame: Measurement completed after the performance of an exercise-heat stress bout and physical performance battery (Heat Tolerance Test 2 – days 6 and 13) both before and immediately after heat acclimation ]
SCAAT lipolysis rate (interstitial glycerol and ethanol output:input) will be collected and assessed for fat mobilization and subcutaneous adipose tissue blood flow during exercise-heat stress bouts

Change in Resting Energy Expenditure and Macronutrient Oxidation [ Time Frame: Measurement completed after the performance of an exercise-heat stress bout and physical performance battery (Heat Tolerance Test 2 – days 6 and 13) both before and immediately after heat acclimation ]
Participant resting energy expenditure, fat oxidation, and carbohydrate oxidation will be assessed via indirect calorimetry for the measurement of respiratory quotient and respiratory exchange ratio

Change in Circulatory Indicators of Lipid Metabolism – NEFAs [ Time Frame: Throughout study completion, an average of 14 days ]
Blood samples will be collected and assessed for the expression of lipid metabolism biomarker Non-Essential Fatty Acids (NEFAs)

Change in Circulatory Indicators of Lipid Metabolism – Insulin [ Time Frame: Throughout study completion, an average of 14 days ]
Blood samples will be collected and assessed for the expression of lipid metabolism biomarker Insulin

Change in Circulatory Indicators of Lipid Metabolism – IGF-1 [ Time Frame: Throughout study completion, an average of 14 days ]
Blood samples will be collected and assessed for the expression of lipid metabolism biomarker Insulin Growth Factor-1 (IGF-1)

Change in Circulatory Indicators of Stress – Epinephrine [ Time Frame: Throughout study completion, an average of 14 days ]
Blood samples will be collected and assessed for the expression of physiological stress biomarker Epinephrine

Change in Circulatory Indicators of Stress – Norepinephrine [ Time Frame: Throughout study completion, an average of 14 days ]
Blood samples will be collected and assessed for the expression of physiological stress biomarker Norepinephrine

Change in Circulatory Indicators of Stress – Cortisol [ Time Frame: Throughout study completion, an average of 14 days ]
Blood samples will be collected and assessed for the expression of physiological stress biomarker Cortisol

Change in Circulatory RNA Content [ Time Frame: Throughout study completion, an average of 14 days ]
Blood samples will be collected and assessed for intracellular RNA content

Change in Circulatory Indicators of Inflammation – IL-1B [ Time Frame: Measurement completed during the completion of exercise-heat stress bouts (Heat Tolerance Tests 1 [days 5 and 12] and 2 [days 6 and 13]) both before and immediately after heat acclimation ]
Blood samples will be collected and assessed for the expression of inflammatory biomarker IL-1B

Change in Circulatory Indicators of Inflammation – TNF-a [ Time Frame: Measurement completed during the completion of exercise-heat stress bouts (Heat Tolerance Tests 1 [days 5 and 12] and 2 [days 6 and 13]) both before and immediately after heat acclimation ]
Blood samples will be collected and assessed for the expression of inflammatory biomarker TNF-a

Change in Circulatory Indicators of Inflammation – IFN-gamma [ Time Frame: Measurement completed during the completion of exercise-heat stress bouts (Heat Tolerance Tests 1 [days 5 and 12] and 2 [days 6 and 13]) both before and immediately after heat acclimation ]
Blood samples will be collected and assessed for the expression of inflammatory biomarker IFN-gamma

Change in Gut Microbiome Diversity [ Time Frame: Measurement completed prior to the completion of an exercise-heat stress bout (Heat Tolerance Test 2) both before and after heat acclimation ]
Stool samples will be collected and assessed for the impact of gut microbiome diversity on heat intolerance

Change in Saliva Metabolite Expression [ Time Frame: Measurement completed during each exercise-heat stress bout (Heat Tolerance Tests 1 and 2) both before and after heat acclimation as well as the final heat acclimation session (HA5) ]
Saliva samples will be collected and assessed for metabolite expression

Change in Thermal Sensation [ Time Frame: Through study completion, an average of 14 days ]
0-8 Scale (cold to hot) that indicated how cold or hot the participant feels. 0 = extremely cold, 8 = extremely hot

Change in Recovery [ Time Frame: Throughout study completion, an average of 14 days ]
Participants will be provided a WHOOP strap after the completion of their baseline visit and will be instructed on how to download the associated application and use of the device. The WHOOP device will be used to provide data on sleep quality and quantity, strain, and recovery

Source: View full study details on ClinicalTrials.gov

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January 11, 2023Comments OffCardiology | Cardiology Clinical Trials | Cardiology Studies | ClinicalTrials.gov | Drug Trials Near Me | US National Library of Medicine
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