NCT07298863 · PepsiCo Global R&D
The Effect of Hydration Status on Substrate Oxidation at Rest and During Light and Moderate Exercise
What this study is about
Metabolic flexibility is the ability to properly switch between fat and carbohydrate stores to use for energy under different conditions (rest, feeding, exercise). Impairments in metabolic flexibility, also known as metabolic inflexibility, have been suggested to be an underlying cause of metabolic disease, like type 2 diabetes.
View original scientific description
Metabolic flexibility is the ability to properly switch between fat and carbohydrate stores to use for energy under different conditions (rest, feeding, exercise). Impairments in metabolic flexibility, also known as metabolic inflexibility, have been suggested to be an underlying cause of metabolic disease, like type 2 diabetes. Long-term low fluid intake may increase the risk of type 2 diabetes due to insulin resistance, a form of metabolic inflexibility. Further, low fluid intake has been shown to impair the ability to switch fuel preference during exercise. While there is some evidence that low fluid intake may lead to impaired metabolic flexibility, more information is needed. Therefore, the purpose of this study is to evaluate the impact of hydration status on substrate preference at rest and during exercise at varying intensities (light and moderate). Further, we will examine whether biological sex and menstrual cycle phase impact hydration and metabolism under these same conditions.
Interventions
OTHER
Exercise Trial
Perform steady-state cycling exercise for approximately 1 hour at 70-80% of maximal heart rate
OTHER
Experimental Trial
24h after exercise trial, following assigned 24h hydration plan, perform indirect calorimetry followed by 30 min of light cycling (\~50% VO2 max) then 30 min of moderate-high cycling (\~80% VO2 max).
Primary outcome measures
Respiratory Exchange Ratio
Time frame: Measured over the course of exercise bouts performed during the exercise and experimental trials. Compared across DEH, EUH-H2O, and EUH-Electrolyte arms.
VCO2 / VO2 measured using indirect calorimetry measured by metabolic cart (Moxus or similar device) while exercising on cycle ergometer.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Subject is male or female
- If female, subject is not pregnant (based on self-report)
- If female, subject has stopped taking birth control medication or removed long-acting reversible contraceptive \>6 months at start of the study
- If female, subject has normal menstrual cycle (21-35 days)
- If female, subject is willing to track their menstrual cycle
- If female, subject has a smartphone compatible for application to track menstrual cycle (female only) and/or wearable data (females and males)
- Subject is 18-35 years of age, inclusive
- Subject body mass index (BMI) is between 18.5-25 kg/m2
- Subject is at least recreationally active (engaged in moderate-intensity, intermittent, or steady-state exercise at least 3 days per week for at least 60 min at a time)
- Subject is accustomed to cycling for at least 60 min
- Subject does not smoke (or has quit for at least 6 months)
- Subject is not taking medication that may interfere with the study (e.g., diuretics, laxatives, or weight loss drugs)
- Subject has no health conditions that would interfere with the study as indicated on the general health questionnaire (GHQ) e.g. cardiovascular, renal, or metabolic diseases
- Subject is not actively involved in weight loss intervention (dieting and/or anti-obesity medications)
- Subject is not allergic to adhesives (e.g., medical tape)
- Subject is willing to avoid alcohol consumption 24 hours prior to visit(s)
- Subject is willing to fast overnight (\~8-12 hours)
- Subject is willing to refrain from vigorous exercise for 24 hours (light physical activity only)
- Subject is willing to be shaved at patch or electrode site, if necessary
- Subject is willing to eat the exact same food the day prior to each visit to the laboratory
- Able to speak, write, and read English
- Provision of written consent to participate
Exclusion criteria
- Subject has participated in a clinical trial within the past 30 days
- Subject has participated in any PepsiCo trial within past 36 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
- Subject is allergic to alcohol (alcohol pre pads are used for blood draws
- If female, subject is taking birth control medication or has long-acting reversible contraceptive
- If male, subject is undergoing hormone therapy to alter testosterone levels (injections, transdermal patch, pill, etc.)
- 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.
Where
- Valhalla, New York
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Mar 3, 2026 · Source of record for eligibility and locations