Water Bolus Volumes During Continuous Exercise in Heat

Hydration is important to all individuals including occupational workers who complete physical activity in the heat. Current best practice guidelines suggest drinking a cup of water every 15-20 minutes during activity in a hot environment, but research shows this may not be ideal for best maintaining hydration. The goal of this study is to determine if larger, more frequent water boluses better maintain hydration than smaller, less frequent water boluses during moderate intensity physical activity in the heat.

Study Overview

• Status: Completed
• Conditions: Hyperthermia; Dehydration (Physiology)
• Intervention / Treatment: Other: Hydration protocol - 237 mL water bolus; Other: Hydration protocol - 500 mL water bolus

• Study Type: Interventional
• Enrollment (Actual): 16
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • New York
    • Buffalo, New York, United States, 14214
      • Center for Research and Exercise in Special Environments

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 39 years (ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: Male

Description

Inclusion Criteria:

• Male
• 18-39 y old
• Self-reported to be healthy

Exclusion Criteria:

• Female
• Not within defined age range
• History of any cardiovascular, neurologic, or metabolic disease
• Current tobacco use or regular use within the last 2 years.
• Taking medications with known thermoregulatory or cardiovascular effects (e.g., aspirin, beta blockers, diuretics, psychotropics, etc.)
• Inability to follow the rules of the protocols or understand the consent form

Study Plan

How is the study designed?

Design Details

• Primary Purpose: PREVENTION
• Allocation: RANDOMIZED
• Interventional Model: CROSSOVER
• Masking: NONE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
ACTIVE_COMPARATOR: Current Best Practice - 237 mL water bolus	Other: Hydration protocol - 237 mL water bolus; Subjects consume 237 mL of water every 20 minutes during 2 hours of high intensity work in the heat.
EXPERIMENTAL: New Intervention - 500 mL water bolus	Other: Hydration protocol - 500 mL water bolus; Subjects consume 500 mL of water every 40 minutes during 2 hours of high intensity work in the heat.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percent body mass loss	Percent body mass loss after water intake	2 hours
Core temperature	Core temperature after water intake	2 hours

Collaborators and Investigators

• Sponsor: State University of New York at Buffalo

Study record dates

Study Major Dates

• Study Start (ACTUAL): April 17, 2019
• Primary Completion (ACTUAL): March 12, 2020
• Study Completion (ACTUAL): March 12, 2020

Study Registration Dates

• First Submitted: October 30, 2020
• First Submitted That Met QC Criteria: November 2, 2020
• First Posted (ACTUAL): November 3, 2020

Study Record Updates

• Last Update Posted (ACTUAL): November 3, 2020
• Last Update Submitted That Met QC Criteria: November 2, 2020
• Last Verified: October 1, 2020

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pathologic Processes; Metabolic Diseases; Wounds and Injuries; Body Temperature Changes; Heat Stress Disorders; Water-Electrolyte Imbalance; Hyperthermia; Dehydration
• Other Study ID Numbers: STUDY00003387

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: IPD data can be provided upon written request.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No