How hydration affects fuel use at rest and during light and moderate exercise
The Effect of Hydration Status on Substrate Oxidation at Rest and During Light and Moderate Exercise
This project will test whether being well-hydrated versus mildly dehydrated changes whether your body uses fat or carbohydrates at rest and during light and moderate cycling, and whether sex and menstrual cycle phase make a difference.
Quick facts
| Phase | Not applicable |
|---|---|
| Study type | Interventional |
| Enrollment | 74 (estimated) |
| Ages | 18 Years to 35 Years |
| Sex | All |
| Sponsor | PepsiCo Global R&D Industry-sponsored |
| Locations | 1 site (Valhalla, New York) |
| Trial ID | NCT07298863 on ClinicalTrials.gov |
What this trial studies
This interventional protocol compares three hydration conditions to measure substrate oxidation at rest and during light and moderate-intensity cycling. Healthy adults aged 18–35 with BMI 18.5–25 who are recreationally active and accustomed to cycling will complete laboratory visits with metabolic testing, wearable data collection, and controlled hydration procedures. Female participants repeat the three-arm protocol in both follicular and luteal menstrual phases for a total of 13 visits including screening, while male participants complete the protocol once for a total of 7 visits. The trial is conducted at the Gatorade Sports Science Institute and aims to determine how hydration status and sex-based factors affect metabolic flexibility.
Who should consider this trial
Good fit: Ideal candidates are healthy, non-smoking adults age 18–35 with BMI 18.5–25 who are recreationally active, accustomed to cycling, and (for women) have regular menstrual cycles and are off hormonal contraception.
Not a fit: People outside the age or BMI ranges, sedentary individuals, pregnant women, current smokers, those taking interfering medications such as diuretics, or those unable to attend repeated cycling visits are unlikely to benefit from participation.
Why it matters
Potential benefit: If successful, the results could help refine hydration guidance to improve fuel switching during exercise and inform strategies that may reduce long-term metabolic disease risk.
How similar studies have performed: Previous small studies have suggested low fluid intake can impair fuel switching during exercise, but evidence is limited and menstrual cycle effects are less well studied.
Eligibility criteria
Show full inclusion / exclusion criteria
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 this trial is running
Valhalla, New York
- Gatorade Sports Science Institute — Valhalla, New York, United States (Recruiting)
Study contacts
- Study coordinator: Matt Hinkley
- Email: GSSIresearchstaff@pepsico.com
- Phone: 570-574-1858
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.