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Wearable Photoplethysmography for Non-invasive Hydration Assessment

Wearable Photoplethysmography for Non-invasive Hydration Assessment

Status
Recruiting
Phases
Unknown
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT07520344
Enrollment
30
Registered
2026-04-09
Start date
2026-04-01
Completion date
2026-10-01
Last updated
2026-04-09

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Hydration Status

Brief summary

Hydration status during exercise is often determined by measuring body mass change, fluid intake and urine output. However, obtaining these measurements can be an invasive, time-consuming process. Hydration status may be detectable by analyzing blood flow patterns of the superficial (just under the skin) blood vessels. Wearable devices are now abundant among the general population, and despite attempts from several groups, a hydration status metric based on noninvasive wearable device metrics has not been developed. With wearables, a light source connected to an optical sensor transmits and reflects light through the body. The light sensor detects absorption of the light based on wavelength measurements of the detected light. Absorption of specific wavelengths of light energy is dependent upon the amount of oxygenated blood in the vessels. When the vessels expand and relax, the amount of blood volume in the observed tissue increases and decreases potentially causing a shift in the photoplethysmography (PPG) wave detected by the wearable. The shift in the shape of the PPG wave may be detected in a way that indicates the relative change in tissue hydration levels. However, to our knowledge, no wrist worn device that utilizes PPG has been successfully able to predict hydration status. Therefore, this study aims to utilize photoplethysmography (PPG) technology in a wearable device to accomplish this approach to hydration monitoring.

Interventions

OTHERExercise

Perform stationary cycling exercise in the laboratory for 2 30- minute bouts at a standardized exercise intensity (wattage) that elicits 50-80% heart rate max determined by equation (208-(70% of age))

Sponsors

PepsiCo Global R&D
Lead SponsorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
OTHER
Masking
NONE

Intervention model description

An interventional randomized, counterbalanced, cross-over design

Eligibility

Sex/Gender
ALL
Age
18 Years to 45 Years
Healthy volunteers
Yes

Inclusion criteria

* Study subject is 18-45 years of age, inclusive * Subject is male or female * If female, subject is not pregnant, planning to get pregnant, or currently breast feeding * Subject is willing to avoid alcohol consumption 24 hours prior to visit(s) * Able to speak, write, and read English * Provision of written consent to participate * Subject is not taking medication that may interfere with the study, as indicated on the general health questionnaire (GHQ) * Subject has no health conditions that would prevent completion of the trial, as indicated on the GHQ * Subject is willing to fast overnight (no food or beverage, only water, \~8- 10 hours) * Subject is willing to refrain from vigorous exercise for 24 hours * Subject is willing to eat the exact same food the day prior to each visit to the testing site * Subject is willing to undergo fluid restriction to induce dehydration * Subject is willing to wear a wrist worn wearable device for the duration of the study

Exclusion criteria

* Subject has participated or currently enrolled in a clinical trial within the past 30 days * Subject has participated in any PepsiCo trial within the past 3 months * Subject has a condition or is taking medication that the investigator believes would interfere with his/her ability to provide informed consent, comply with the study protocol, which might confound the interpretation of the study results, or put the person at undue risk, as indicated on the GHQ * Subject is employed by, or has a parent, guardian, or other immediate family member employed by a company that manufactures any products that compete with any Gatorade product. If subject is unsure if a company would be considered a competitor to Gatorade, they will be asked to please let the study investigator know the name of the other company and the nature of their relationship to that company before they sign the informed consent. * Subject has a health condition or is taking medication that can be worsened by fluid restriction, as indicated on the GHQ

Design outcomes

Primary

MeasureTime frameDescription
Wearable Sensr DataContinuous data collection over 24 hours from start of exercise trial through completion of Day 2 measurements.photoplethysmogram (PPG) waveform data- optical signals obtained from photoplethysmography, which measure blood volume changes in the microvascular bed of tissue.
Body Mass ChangeChange in body mass during 60 min exercise bout and over 24 hours from baseline

Secondary

MeasureTime frameDescription
Urine Specific GravityDay 1: Baseline, post 1st and 2nd 30 min exercise sessions Day 2: 1st morning void collected at home and upon arrival at laboratoryau
Urine VolumeDay 1: Baseline, post 1st and 2nd 30 min exercise sessions Day 2: 1st morning void collected at home and upon arrival at laboratoryg
Urine ColorDay 1: Baseline, post 1st and 2nd 30 min exercise sessions Day 2: 1st morning void collected at home and upon arrival at laboratoryScale of 1 (most hydrated) to 7 (most dehydrated)
Sweat RateThroughout entire duration of 60 min exercise bout\[Body mass loss (kg) + fluid intake (mL)\]/Duration of exercise (hr)
Fluid Intakedocumented by subject on provided log for 24 hours prior to exercise and experimental trials. Exercise bouts- DEH group restricted from fluid intake. EUH group fluid measured over duration of exercise bout (60 minutes).mL
Subjective Feelings of ThirstDay 1 & 2: Following 5 min of restCategorical Thirst Scale, on a scale of 1 (Not thirsty at all) to 7 (very, very thirsty).
Heart RateAt medical screening to determine eligibility. Day 1: Prior to start of exercise bouts during 5 min rest and every 10 min throughout entire duration of each 60 min exercise trial. Day 2: During 5 min rest, prior to body weight measurement.bpm
Blood pressureMedical Screening to determine eligibilitysystolic/diastolic (mmHg)
Subject DemographicsAt baselineAge, Sex, Race, and Ethnicity
Dietary IntakeCompleted for 24 hours prior to baseline and between visits.Food intake logs
Standardized Exercise IntensityEvery 10 min throughout entire duration of each 30 min exercise bout to reach 50-80% of heart rate max.W
Rate of Perceived ExertionEvery 10 min throughout entire duration of each 30 min exercise boutBorg Scale, a scale of 6 (No exertion at all) to 20 (maximal exertion)

Countries

United States

Contacts

CONTACTAnthony Wolfe
anthony.wolfe@pepsico.com574-315-5901

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Apr 10, 2026