Oral Rehydration Solutions in Healthy Adult Athletes

Inclusion Criteria: * 18 to 30 years of age. * Body fat percentage ≤17% for males and ≤24% for females. * Male or non-pregnant, non-lactating female, at least 6 months postpartum prior to screening visit. * Cycling VO2max in range of 45-53 mL O2/kg/min for males or 36-43 mL O2/kg/min for females. * If female, participant has a regular menstrual cycle, \>21 days and \<35 days in length. * Willing to consume grape-flavored beverages during the study. * If on chronic medication such as lipid-lowering, thyroid medication or hormone therapy, the dosage must be constant for at least 2 months prior to screening and baseline visit. * Weight-stable for the two months prior to screening visit * Voluntarily signed and dated an informed consent form (ICF), approved by an IRB, and provided Health Insurance Portability and Accountability Act (HIPAA) or other applicable privacy regulation authorization prior to any participation in the study. * No known intolerance or allergy to ingredients in study products. * Willing to refrain from using saunas or hot tubs for the duration of the study. * Willing to follow study procedures and complete any forms or assessments needed during the study. Exclusion Criteria: * Athlete in a weight-conscious sport such as but not limited to wrestling, powerlifting, boxing, rowing, gymnastics or any martial arts. * Currently, and for the past 4 weeks or longer: running \>40 miles per week on average, cycling \>80 miles per week on average or swimming \>20,000 yards per week on average. * Participating in another study that has not been approved as a concomitant study. * Uses any form of tobacco or nicotine, or other controlled substance not prescribed by a physician. * Previous history with heat illness or injury that resulted in a visit to a medical center. * Experienced a serious musculoskeletal injury or surgery in the past 6 months that poses a risk during the trial, according to the study investigator. * Eating disorder, severe dementia or delirium, history of significant neurological or psychiatric disorder, alcoholism, substance abuse or other conditions that may interfere with study product consumption or compliance with study protocol procedures. * Currently taking or has taken antibiotics within 6 weeks of enrollment. * Currently taking or has taken a diuretic within 1 week of enrollment. * Diagnosed with the following according to medical records, self-report or according to the clinician's judgment: * Acute or chronic infections including but not restricted to respiratory infections, diarrhea, Hepatitis B or C, HIV infection or tuberculosis * Severe gastrointestinal disorders such as celiac disease, short bowel syndrome, pancreatic insufficiency, or cystic fibrosis * Cardiovascular, metabolic \[including diabetes\], renal, hepatic, or respiratory disease * Active malignancy * Polycystic ovary disease * Any other clinically significant medical condition, which in the investigator's opinion, makes him or her unsuitable for inclusion in the study.