To determine the effects 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 550 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 and in urine (60 min). 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 Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
BASIC_SCIENCE
Masking
DOUBLE
Enrollment
17
The composition of sport drinks will be manipulated to determine the effect of drink composition on the appearance of ingested water in body fluid.
Loughborough University
Loughborough, Leicestershire, United Kingdom
Time at which drink absorption rate was maximum (t1)
Determined from D2O values in venous blood samples collected before and after drink ingestion
Time frame: 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
Time frame: 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
Time frame: 60 minutes
Maximum absorption rate of drink
Determined from D2O values in venous blood samples collected before and after drink ingestion
Time frame: 60 minutes
Area under the curve for D2O
Determined from D2O values in venous blood samples collected before and after drink ingestion
Time frame: 60 minutes
Plasma volume
Determined from haemoglobin and haematocrit measures in venous blood samples collected before and after drink ingestion
Time frame: 60 minutes
Plasma osmolality
Determined from venous blood samples collected before and after drink ingestion
Time frame: 60 minutes
Plasma sodium concentration
Determined from venous blood samples collected before and after drink ingestion
Time frame: 60 minutes
Plasma potassium concentration
Determined from venous blood samples collected before and after drink ingestion
Time frame: 60 minutes
Plasma glucose concentration
Determined from venous blood samples collected before and after drink ingestion
Time frame: 60 minutes
Plasma lactate concentration
Determined from venous blood samples collected before and after drink ingestion
Time frame: 60 minutes
Plasma creatinine concentration
Determined from venous blood samples collected before and after drink ingestion
Time frame: 60 minutes
Plasma amino acid concentration
Determined from venous blood samples collected before and after drink ingestion
Time frame: 60 minutes
Urinary D2O concentration
Determined from urine samples collected before and after drink ingestion
Time frame: 60 minutes
Urinary specific gravity
Determined from urine samples collected before and after drink ingestion
Time frame: 60 minutes
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.