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The Effect of Manipulating Hydration Status During Cycling in the Heat on Acute Kidney Injury Biomarkers

Not Applicable
Completed
Conditions
Hypohydrated
Euhydrated
Interventions
Other: Water intake
Registration Number
NCT04140045
Lead Sponsor
Loughborough University
Brief Summary

Acute Kidney Injury (AKI) is common in prolonged endurance events. Risk factors for exercise-associated AKI include: the exercise itself, heat, hypohydration, muscle breakdown and non-steroidal anti-inflammatory drug (NSAID) use. Prior research from our laboratory showed the hypohydration during high-intensity running increased a biomarker of AKI (urine osmolality-corrected kidney injury molecule 1). Therefore, the current study will now investigate the effect of manipulating hydration status during cycling on biomarkers of AKI.

Detailed Description

Not available

Recruitment & Eligibility

Status
COMPLETED
Sex
Male
Target Recruitment
14
Inclusion Criteria
  • Healthy
  • recreationally active
Exclusion Criteria
  • Smoker/vaper
  • regular use of anti-inflammatory medications (e.g. ibuprofen)
  • history of kidney disease or diabetes

Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Arm && Interventions
GroupInterventionDescription
EuhydratedWater intakeParticipants will be provided with water intake that matches their sweat losses during cycling in the heat (90-120 minutes at 35°C)
HypohydratedWater intakeParticipants will be required to restrict their water intake during cycling in the heat (90-120 minutes at 35°C), in order to achieve a body mass loss of approximately 3%.
Primary Outcome Measures
NameTimeMethod
Changes in urinary neutrophil gelatinase-associated lipocalin (uNGAL) (uncorrected/raw values and urine osmolality-corrected values)Pre-exercise (baseline), post-exercise (immediately after the intervention), 24 hours post-baseline

A novel protein biomarker for acute kidney injury

Changes in serum creatininePre-exercise (baseline), post-exercise (immediately post-exercise), 24 hours post-baseline

Serum creatinine is a marker of kidney function

Changes in urinary Kidney Injury Molecule 1 (uKIM-1) (uncorrected/raw values and urine osmolality-corrected values)Pre-exercise (baseline), post-exercise (immediately after the intervention), 24 hours post-baseline

A novel protein biomarker for acute kidney injury

Changes in urine osmolalityPre-exercise (baseline) and post-exercise (immediately after the intervention), as well as all urine produced from post-exercise until 24 hours post-baseline

A measure of urine concentration.

Incidence of Acute Kidney Injury (as determined by changes in serum creatinine)Pre-exercise (baseline), post-exercise (immediately post-exercise), 24 hours post-baseline

A rise in serum creatinine of 1.5 fold or more from baseline will be defined as acute kidney injury

Secondary Outcome Measures
NameTimeMethod
Changes in creatine kinasePre-exercise (baseline), post-exercise (immediately after the intervention), 24 hours post-baseline

A marker of muscle damage

Changes in nausea scorespre-exercise (baseline), every 30 minutes during exercise (30, 60,90 and 120 minutes), post-exercise (immediately after the intervention) and 24 hours post-baseline

Participants will be asked to rate their nausea on a scale of 0-10, with higher scores meaning a worse outcome .

Changes in stomach fullness scorespre-exercise (baseline), every 30 minutes during exercise (30, 60,90 and 120 minutes), post-exercise (immediately after the intervention) and 24 hours post-baseline

Participants will be asked to rate their stomach fullness on a scale of 0-10, with higher scores meaning a worse outcome .

Plasma volume changesPre-exercise (baseline), post-exercise (immediately after the intervention), 24 hours post-baseline
Body mass changespre-exercise (baseline), throughout exercise, post-exercise (immediately after the intervention), 24 hours post-baseline
Changes in thirst scorespre-exercise (baseline), every 30 minutes during exercise (30, 60,90 and 120 minutes), post-exercise (immediately after the intervention) and 24 hours post-baseline

Participants will be asked to rate their thirst on a scale of 0-10, with higher scores meaning a worse outcome .

Changes in thermal comfort scorespre-exercise (baseline), every 30 minutes during exercise (30, 60,90 and 120 minutes), post-exercise (immediately after the intervention) and 24 hours post-baseline

Participants will be asked to rate their thermal comfort on a scale of -10 to 10, with -10 being cold impossible to bear and 10 being heat impossible to bear

Changes in stomach bloatedness scorespre-exercise (baseline), every 30 minutes during exercise (30, 60,90 and 120 minutes), post-exercise (immediately after the intervention) and 24 hours post-baseline

Participants will be asked to rate their stomach bloatedness on a scale of 0-10, with higher scores meaning a worse outcome .

Changes in serum osmolalityPre-exercise (baseline), post-exercise (immediately after the intervention), 24 hours post-baseline

The gold standard marker of hydration status

Changes in lactate dehydrogenasePre-exercise (baseline), post-exercise (immediately after the intervention), 24 hours post-baseline

A marker of muscle damage

Ad libitum energy (Kj), carbohydrate (g), sugar (g), protein (g), fat (g), saturated fat (g), sodium (g) and water intake (g).from post-exercise (immediately after the intervention) until 24 hours post-baseline

Participants will complete a weighed food and fluid diary, using a set of food scales and a diary, to record all food and fluid that they ingest. This data will then be analysed using dietary analysis software (e.g. Nutritics)

Changes in headache scorespre-exercise (baseline), every 30 minutes during exercise (30, 60,90 and 120 minutes), post-exercise (immediately after the intervention) and 24 hours post-baseline

Participants will be asked to rate their headache on a scale of 0-10, with higher scores meaning a worse outcome .

Changes in dizziness scorespre-exercise (baseline), every 30 minutes during exercise (30, 60,90 and 120 minutes), post-exercise (immediately after the intervention) and 24 hours post-baseline

Participants will be asked to rate their dizziness on a scale of 0-10, with higher scores meaning a worse outcome .

Changes in gastrointestinal comfort scorespre-exercise (baseline), every 30 minutes during exercise (30, 60,90 and 120 minutes), post-exercise (immediately after the intervention) and 24 hours post-baseline

Participants will be asked to rate their gastrointestinal comfort on a scale of 0-10, with higher scores meaning a worse outcome .

Changes in urge to vomit scorespre-exercise (baseline), every 30 minutes during exercise (30, 60,90 and 120 minutes), post-exercise (immediately after the intervention) and 24 hours post-baseline

Participants will be asked to rate their urge to vomit on a scale of 0-10, with higher scores meaning a worse outcome .

Changes in urinary creatininepre-exercise (baseline), post-exercise (immediately after the intervention) and 24 hours post-baseline
Changes in heart rateWill be monitored throughout the exercise intervention, at 15 minute intervals (15 minutes, 30 minutes, 45 minutes, 60 minutes, 75 minutes, 90 minutes, 105 minutes and 120 minutes)

Provides insight into exercise intensity

changes in rating of perceived exertionWill be monitored throughout the exercise intervention, at 30 minute intervals (30 minutes, 60 minutes, 90 minutes and 120 minutes)

Provides insight into exercise intensity

Changes in aural temperatureWill be determined immediately prior to the exercise intervention (at rest) and then throughout the exercise intervention at 15 minute intervals (15 minutes, 30 minutes, 45 minutes, 60 minutes, 75 minutes, 90 minutes, 105 minutes and 120 minutes)

in-ear temperature

Trial Locations

Locations (1)

Loughborough University

🇬🇧

Loughborough, United Kingdom

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