Effect of Amino Acid Addition to a Drink on the Appearance of Ingested Water in Body Fluids1

Effect of Amino Acid Addition to a Drink on the Appearance of Ingested Water in Body Fluids

To determine the effects of a moderate amount of amino acids on the rate of water absorption and availability as a precursor fluid for sweat. Young and healthy (male or female) volunteers will take part in three experimental trials. In each trial, volunteers will be given one of two commercially available sports drinks or a commercially available sport drink with added amino acids in a double-blinded, randomised, crossover design. Each drink will be a single 600 mL bolus. All beverages will be labelled with deuterium (D2O). Trials will be compared for temporal accumulation of deuterium in plasma over the course of 60 minutes. Whole blood measurements of haemoglobin and haematocrit will also be made and plasma volume changes calculated. It is hypothesised that the amino acid trial will increase the rate of fluid absorption.

Study Overview

• Status: Completed
• Conditions: Rate of Water Appearance/Delivery in the Blood Water Balance
• Intervention / Treatment: Other: Composition of Sports Drink

• Study Type: Interventional
• Enrollment (Actual): 15
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United Kingdom
  • Leicestershire
    • Loughborough, Leicestershire, United Kingdom, LE11 3TU
      • Loughborough University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 50 years (Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Generally fit and healthy (determined by health screen questionnaire)
• Recreationally active (minimum 3 hours of physical activity per week including walking)

Exclusion Criteria:

• Any cardiovascular, gastrointestinal, renal or acute/chronic health conditions that may influence the outcomes
• Smoking (including vaping)
• BMI of greater than 30 (combined with a body fat percentage greater than 20%) or BMI lower than 17.5

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Double

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Commercially Available Sports Drink A; A commercially available flavored electrolyte solution, The Coca-Cola Company	Other: Composition of Sports Drink; The composition of sport drinks will be manipulated to determine the effect of drink composition on the appearance of ingested water in body fluid.
Experimental: Commercially Available Sports Drink B; A commercially available flavored electrolyte solution, PepsiCo	Other: Composition of Sports Drink; The composition of sport drinks will be manipulated to determine the effect of drink composition on the appearance of ingested water in body fluid.
Experimental: Commercially Available Sports Drink A with added Amino Acids; he same as sports drink A above (a commercially available flavored electrolyte solution, The Coca-Cola Company), but with the addition of a small amount of amino acids (~2.6 g/100 ml).	Other: Composition of Sports Drink; The composition of sport drinks will be manipulated to determine the effect of drink composition on the appearance of ingested water in body fluid.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Time at which drink absorption rate was maximum (t1)	Determined from D2O values in venous blood samples collected before and after drink ingestion	60 minutes
Time at which drink absorption rate returned to 0 (t2)	Determined from D2O values in venous blood samples collected before and after drink ingestion	60 minutes
Time at which 50% of drink was absorbed (t1/2)	Determined from D2O values in venous blood samples collected before and after drink ingestion	60 minutes
Maximum absorption rate of drink	Determined from D2O values in venous blood samples collected before and after drink ingestion	60 minutes
Area under the curve for D2O	Determined from D2O values in venous blood samples collected before and after drink ingestion	60 minutes

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Plasma volume	Determined from haemoglobin and haematocrit measures in venous blood samples collected before and after drink ingestion	60 minutes
Plasma osmolality	Determined from venous blood samples collected before and after drink ingestion	60 minutes
Plasma glucose concentration	Determined from venous blood samples collected before and after drink ingestion	60 minutes
Plasma lactate concentration	Determined from venous blood samples collected before and after drink ingestion	60 minutes
Plasma creatinine concentration	Determined from venous blood samples collected before and after drink ingestion	60 minutes
Plasma amino acid concentration	Determined from venous blood samples collected before and after drink ingestion	60 minutes
Urinary specific gravity	Determined from urine samples collected before and after drink ingestion	60 minutes

Collaborators and Investigators

• Sponsor: Loughborough University
• Collaborators: Entrinsic Beverage Company LLC

Study record dates

Study Major Dates

• Study Start (Actual): February 12, 2021
• Primary Completion (Actual): May 1, 2021
• Study Completion (Actual): May 1, 2021

Study Registration Dates

• First Submitted: February 12, 2021
• First Submitted That Met QC Criteria: March 23, 2021
• First Posted (Actual): March 26, 2021

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: February 4, 2025
• Last Verified: January 1, 2023

More Information

Terms related to this study

• Other Study ID Numbers: LEON3151

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No