Can a drink beat water for rehydration? a new trial puts electrolyte formulas to the test

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Body mass index (BMI) between 17.0-29.9 kg/m2 (not obese) * Resting heart rate less than 90 beats per minute; although, if less than 40 beats per minute subject must get clearance from a medical professional * Not hypertensive (Systolic \<140 mmHg and Diastolic \<90 mmHg) * Have not had in the 3 months prior to screening or planning to have a major surgery during study period * Physically capable and willing to ingest the assigned amount of fluid while cycling and at rest for visits 3, 4, and 5 * Must be moderately trained; engage in moderate intensity, intermittent, or steady-state exercise at least 3 days per week for at least one hour at a time. * Willing to maintain the same level of physical activity throughout the study period, except during the 24 hour period prior to each study visit. * Achieve a peak maximal oxygen consumption at screening that is at least 60% of their age and gender matched normative value per American College of Sports Medicine recommendations. * Capable of completing 90 minutes of self-paced stationary cycling (\~70-80% max heart rate) in a heated environmental chamber (\~30-32°C (86-89°F) with \~50% RH). * Can drink a minimum of 2.0 L fluid (if female) or 2.5 L fluid (if male) the day prior to test visits * For visits 3-5, subjects must have a urine specific gravity less than 1.020. * For visit 3-5, subject must not have exercised within 24 hours of visit * Consume no more than two standard alcoholic drinks per day on a regular basis and during study period. * Maintain diet, exercise, BMI, medication, and dietary supplements throughout study period as changes may alter hydration and electrolyte levels and result in changes to outcome measures. Exclusion Criteria: * If female, lactating, pregnant or planning to become pregnant during the study. * Have a known sensitivity or allergy to any of the study products * Have a history of diabetes * Have a history of known cardiovascular disease * Have a history of a diagnosis of celiac disease, chronic pancreatitis, steatorrhea, unstable thyroid disease, immune disorder (i.e., HIV/AIDS), cancer (except localized skin cancer without metastases or in situ cervical cancer within 5 years prior to screening visit). * Have an active or uncontrolled diseases or conditions * Have had a current or previous Corona virus disease 2019 diagnosis in the three months prior to screening. * Have any medical conditions that may impact ability to exercise or ability to ingest prescribed fluid volume as determined by the study nurse, including infection or illness * Weighing less than 80 lbs at any visit; although very unlikely, we need to maintain this cut off, as too low a body mass is unhealthy. * Has taken within 30 days or within seven half-lives (whichever is longer) of first test visit: selective serotonin uptake inhibitors (SSRI), Apremilast, caffeine-containing drugs, Corticosteroids (systemic use), Decongestants, Diuretics, Laxatives, Muscle relaxants, Opioid painkillers, Statins, Oral antibiotics * Has taken within 30 days of first test visit: Calcium, Dandelion, Lithium orotate, Potassium citrate, Watercress, Inhalables smokables, or the like cigarettes, vaporizers, water pipes, or cannabis * Has taken within 24 hours prior to test visit: Alcohol, Caffeine (including coffee, tea, energy drinks, etc. prohibited in the 12hrs prior to each dose of the study product), Laxatives, Diuretics, or Sports drinks (electrolyte drinks) * received or use test product(s) in another research study in the 28 days prior to baseline visit (Familiarization, Visit/Visit 2), or longer if the previous test product is deemed by the investigator to have lasting effects that might influence the eligibility criteria or outcomes of the current study. * have any other active or unstable medical conditions or use medications, supplements, or therapies that, in the opinion of the investigator, may adversely affect the participant's ability to complete the study or its measures or pose a significant risk to the participant.