Predicting Responses to Exhausting, Prolonged, And Repeated Exercise Demands (PREPARED) for Heat

NCT06475339 | Recruiting

• 2 other identifiers: STUDY00007981CDMRP-BA230031
• Study Type: interventional
• Target: 24
• Locations: 1 country
• Sites: 1

Brief Summary

The overall goal of this project is to identify a work/rest cycle that allows for faster mission completion needed in emergency situations, compared to current Army heat guidance, while mitigating heat strain and neuromuscular fatigue. This project will determine the trade-off between faster mission completion and risk of heat strain and physical performance decrements. Completion of this project will allow military leaders to make informed decisions by understanding the impact of their choices on the magnitude of physical performance decrements and expected heat casualties, setting up hot weather missions for success.

Conditions

Hyperthermia; Fatigue; Heat

Outcome Measures

Primary Outcomes (2)

• Core temperature

  Maximum gastrointestinal temperature reached during the work protocol

  180 minutes of work

• Isometric mid-thigh pull strength

  Maximum voluntary contraction strength assessed using a force plate

  180 minutes of work

Secondary Outcomes (4)

• Metabolic cost

  180 minutes of work

• Heart rate

  180 minutes of work

• Mean skin temperature

  180 minutes of work

• Vastus lateralis electromyography

  180 minutes of work

Study Arms (4)

30/30 work/rest cycle first

ACTIVE COMPARATOR

Participants will first complete the 30/30 work/rest cycle, and then complete the other three conditions in a randomized fashion

Other: 30/30 work/rest cycle; Other: 30/20 work/rest cycle; Other: 40/30 work/rest cycle; Other: 20/12 work/rest cycle

30/20 work/rest cycle first

EXPERIMENTAL

Participants will first complete the 30/20 work/rest cycle, and then complete the other three conditions in a randomized fashion

Other: 30/30 work/rest cycle; Other: 30/20 work/rest cycle; Other: 40/30 work/rest cycle; Other: 20/12 work/rest cycle

40/30 work/rest cycle first

EXPERIMENTAL

Participants will first complete the 40/30 work/rest cycle, and then complete the other three conditions in a randomized fashion

Other: 30/30 work/rest cycle; Other: 30/20 work/rest cycle; Other: 40/30 work/rest cycle; Other: 20/12 work/rest cycle

20/12 work/rest cycle first

EXPERIMENTAL

Participants will first complete the 20/12 work/rest cycle, and then complete the other three conditions in a randomized fashion

Other: 30/30 work/rest cycle; Other: 30/20 work/rest cycle; Other: 40/30 work/rest cycle; Other: 20/12 work/rest cycle

Interventions

30/20 work/rest cycle OTHER

Participants will walk on a treadmill while wearing a weighted backpack to a work/rest cycle of 30 minutes of work followed by 20 minutes of rest.

20/12 work/rest cycle first; 30/20 work/rest cycle first; 30/30 work/rest cycle first; 40/30 work/rest cycle first

40/30 work/rest cycle OTHER

Participants will walk on a treadmill while wearing a weighted backpack to a work/rest cycle of 40 minutes of work followed by 30 minutes of rest.

20/12 work/rest cycle first; 30/20 work/rest cycle first; 30/30 work/rest cycle first; 40/30 work/rest cycle first

20/12 work/rest cycle OTHER

Participants will walk on a treadmill while wearing a weighted backpack to a work/rest cycle of 20 minutes of work followed by 12 minutes of rest.

20/12 work/rest cycle first; 30/20 work/rest cycle first; 30/30 work/rest cycle first; 40/30 work/rest cycle first

30/30 work/rest cycle OTHER

Participants will walk on a treadmill while wearing a weighted backpack to a work/rest cycle of 30 minutes of work followed by 30 minutes of rest.

20/12 work/rest cycle first; 30/20 work/rest cycle first; 30/30 work/rest cycle first; 40/30 work/rest cycle first

Eligibility Criteria

• Age: 18 Years - 39 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Healthy individuals
• Physically active

You may not qualify if:

• History of cardiovascular, metabolic (such as clinical thyroid disease), respiratory, neural, or renal disease
• Hypertensive (systolic blood pressure \> 139 mmHg, diastolic blood pressure \> 89 mmHg) or tachycardic (heart rate \> 100 bpm) during the screening visit
• Taking medications or supplements known to effect physiologic responses to exercise or thermoregulation (e.g., beta blockers, omega-3 fatty acids, statins, aspirin)
• Tobacco or nicotine use currently or in the past six months
• Musculoskeletal injury expected to impact exercise in the protocol
• A positive pregnancy test at any point in the study
• Study physician discretion based on any other medical condition or medication
• Inability to understand or follow instructions or the protocol
• Gastrointestinal disease or previous surgery prohibiting core temperature capsule use. Participants with a contraindication can opt to insert the pill rectally as a suppository.

Sponsors & Collaborators

• State University of New York at Buffalo: lead
• United States Department of Defense: collaborator

Study Sites (1)

Center for Research and Education in Special Environments

Buffalo, New York, 14214, United States

RECRUITING

MeSH Terms

Conditions

Hyperthermia; Heat Stress Disorders

Condition Hierarchy (Ancestors)

Body Temperature Changes; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Wounds and Injuries

Study Officials

• Riana R Pryor, PhD

  University at Buffalo

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Riana R Pryor, PhD

CONTACT

7168295456; rpryor@buffalo.edu

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor

Study Record Dates

• First Submitted: June 14, 2024
• First Posted: June 26, 2024
• Study Start: November 1, 2024
• Primary Completion (Estimated): March 1, 2027
• Study Completion (Estimated): March 1, 2027
• Last Updated: January 26, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)