The Impact of Self-assessment on Hydration

NCT06954909 | Enrolling By Invitation

• 1 other identifier: EMW-2022- FP-00082
• Study Type: interventional
• Target: 38
• Locations: 1 country
• Sites: 1

Brief Summary

The studies objective is to assess the efficacy of hydration education and the use of a self-assessment worksheet vs. a no-intervention control on improving fluid intake and hydration status in underhydrated wildland firefighters (WLFFs) and their surrogates. Part I allows to understand hydration status of the participants (screening phase), Part II confirms if participants indeed are deemed to be low fluid consumers, and Part III of this research is a clinical trial that will focus on the optimization of hydration by improving fluid intake (and as a result lowering urine concentration) allowing participants theoretically to improve exercise performance (acute) and optimize health on the long term.

Conditions

Hydration Status

Keywords

Urine osmolality; Urine specific gravity; Labelled water (D20); Deuterium; Education; Self-assessment; Tactical operators; Firefighters; Women; Men; Healthy subjects

Outcome Measures

Primary Outcomes (2)

• Fluid turnover

  Fluid turnover based on D2O analysis

  Over a period of 4 days, in two 48-hour segments.

• Urine concentration

  Urine concentration (osmolality).

  Afternoon sample day 1, morning sample day 2/4/6

Secondary Outcomes (8)

• Urine concentration

  Afternoon sample day 1, morning (and potential afternoon) samples day 1/2/3/4/5/6.

• Activity

  Throughout the study during working hours, which may vary between 8-16 hours per working day.

• Hydration strategy

  Day 6 of the data collection, covering the hydration strategy during the study period.

• Heat stress

  Throughout the study during working hours, which may vary between 8-16 hours per working day.

• INT: Self-reported hydration measures

  Study days 2/3/4/5/6.

Other Outcomes (4)

• Demographics

  Measured at the start of the study during Part I (screening phase).

• Environmental conditions

  Throughout the study during working hours, which may vary between 8-16 hours per working day.

• Environmental conditions

  Throughout the study during working hours, which may vary between 8-16 hours per working day.

Study Arms (2)

Hydration education and hydration self-assessment

EXPERIMENTAL

Participants will participate in a 25-minute hydration education session that also includes instruction about how the use the hydration self-assessment worksheets and materials.

Behavioral: Hydration education and self-assessment

No Hydration education and hydration self-assessment (business as usual)

NO INTERVENTION

Participants do not participate in any education or self-assessment, other than applying their normal hydration strategies.

Interventions

Hydration education and self-assessment BEHAVIORAL

Hydration education is a 25-minute session based on the theory of planned behavior, including the instructions how to use a worksheet for hydration self-assessment and materials.

Hydration education and hydration self-assessment

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may not qualify if:

• Age 18-65 years
• Identifying as male, female or other
• Thyroid medication
• Bariatric surgery
• Cardiovascular disease
• Renal disease
• Hepatic disease
• Bodyweight \<110 lbs.
• Any injury that would not allow physical performance or activity
• Pregnant or lactating
• Diuretics
• Non-stable self-reported body weight for the last month (\<10 lbs. fluctuation)
• Investigators will not exclude participants reporting the use of dietary supplements as there is no evidence that the accuracy of self-assessment (specifically the accuracy of urine color assessment) to determine a low vs. high urine concentration is influenced by dietary supplement use, but participants will be questioned about their supplement, electrolyte and sport drink use.

Sponsors & Collaborators

• Arizona State University: lead
• Federal Emergency Management Agency: collaborator

Study Sites (1)

ASU Health Futures Center

Phoenix, Arizona, 85054, United States

Location

Related Publications (1)

• Wardenaar FC, Thompsett D, Vento KA, Bacalzo D. A lavatory urine color (LUC) chart method can identify hypohydration in a physically active population. Eur J Nutr. 2021 Aug;60(5):2795-2805. doi: 10.1007/s00394-020-02460-5. Epub 2021 Jan 8.

  PMID: 33416980 BACKGROUND

MeSH Terms

Conditions

Multiple Endocrine Neoplasia Type 1

Interventions

Diagnostic Self Evaluation

Condition Hierarchy (Ancestors)

Multiple Endocrine Neoplasia; Endocrine Gland Neoplasms; Neoplasms by Site; Neoplasms; Neoplasms, Multiple Primary; Neoplastic Syndromes, Hereditary; Genetic Diseases, Inborn; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Endocrine System Diseases

Intervention Hierarchy (Ancestors)

Diagnostic Techniques and Procedures; Diagnosis

Study Design

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

Model Details: Allocation to intervention (INT) or control (CON) depends on the total number of participants at different locations that will be eligible. The investigators will try to match participants based on their sex, age and bodyweight, and then randomly assign these matched participants to the intervention or control group. The control group participants will be offered to follow the education session after data collection has been finished.

Study Record Dates

• First Submitted: April 17, 2025
• First Posted: May 2, 2025
• Study Start: April 22, 2025
• Primary Completion: February 12, 2026
• Study Completion: February 13, 2026
• Last Updated: January 28, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)