Effect of Adding Glycerol to Electrolyte Beverages on Fluid Balance in Healthy Euhydrated Men and Women at Rest

The results of a prior study PEP-2311 suggested there was a positive dose-response effect of glycerol and sodium on fluid balance and fluid retention. In addition, inclusion of glycerol resulted in an upward shift in the relationship between sodium concentration and fluid balance. The practical interpretation is that addition of glycerol enables a reduction in sodium concentration compared with a 0% glycerol drink.

In this follow-up study, the investigators hypothesize that 1) fluid balance will be sustained (greater than or not different from baseline) and significantly greater than placebo for 120 min after drinking the test no/low/moderate carbohydrate beverages and 2) fluid balance will not differ between the carbohydrate-electrolyte beverages, but both will be greater than placebo.

This is a two-part study. Subjects will be asked to complete either Part 1 or Part 2 of this study. Subjects can participate in both parts of the study if they are interested and available to complete all trials. However, they will be asked to complete Part 1 before enrolling in Part 2 of the study. Dosing days are separated by 2-15 days.

Objective 1) To compare the effect of consumption of four no/low/moderate carbohydrate drinks with high electrolyte concentrations vs. placebo on fluid balance at rest. To enroll N=25

Objective 2) To compare the effect of consumption of two moderate carbohydrate drinks with low electrolyte concentrations vs. placebo on fluid balance at rest. To enroll N=70

Eligibility Criteria:
Inclusion Criteria:

Subject is male or female

* If female, subject is not pregnant (based on self-report)
* Subject is 18-50 years of age, inclusive Subject is at least recreationally active (engaged in light to moderate intensity, intermittent, or steady-state exercise at least 3 days per week for at least 30 min at a time)
* 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)
* 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 allergic to adhesives (e.g., medical tape)
* Subject is not allergic to kiwi-strawberry flavoring
* 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 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 6 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 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.