Home › Acute Kidney Injury › NCT07472426

Effects of Creatine Supplementation on Cognitive Measures and Markers of Acute Kidney Injury After Exercise in the Heat

Who can join

Ages 18 to 45 · All sexes · Healthy volunteers welcome

Inclusion Criteria:

* Age range: 18-45 years old
* Physical Activity Level: Classified as 'active' using the criteria of engaging in planned exercise at least 3x/week, for a minimum of 30 minutes per session, over the past 3 months
* Aerobic Fitness Level: Subjects must have an aerobic fitness classification of at least 'good' per American College of Sports Medicine (ACSM) criteria and assessed via maximal oxygen uptake test
* Health Status: Free of any known cardiovascular, metabolic, renal, or neurologic conditions.
* Physical Limitations: Indicates no physical limitations to cycling for \~ 90 minutes
* Supplementation: Reports no use of creatine within the past 4 weeks
* Recent Illness: Reports no presence of illness, vomiting, or diarrhea in the previous three days.

Exclusion Criteria:

* Known allergy to creatine or maltodextrin.
* History of adverse heat-related events (e.g., heat exhaustion, heat stroke, severe dehydration requiring medical intervention)
* Reports use of medications or supplements that may interfere with thermoregulation, heart rate, kidney injury or blood pressure responses during exercise (e.g. NSAID)

About the study

The goal of this clinical trial is to learn if one week of creatine monohydrate supplementation alters inflammation, markers of acute kidney injury (AKI) risk, and cognitive performance in active, young, healthy volunteers. The main questions it aims to answer are:

1. Does one-week of creatine supplementation alter urinary markers of inflammation (cytokines) during exercise in the heat when compared to placebo? 2. Does one-week of creatine supplementation alter markers of AKI during exercise in the heat when compared to placebo? 3. Does one-week of creatine supplementation attenuate reductions in cognitive measures as a response of fatigue from exertional heat stress.

Researchers will compare creatine monohydrate to a placebo (maltodextrin) to see if it alters inflammation, risk of acute kidney injury, and cognition after exercise in the heat.

Participants will :

* Complete a baseline aerobic exercise test to measure VO2max * Ingest 20 grams per day of creatine monohydrate or placebo (maltodextrin) for seven consecutive days * Cycle for 90 minutes in a heated chamber (38 C, \~40% relative humidity), alternating low- and high-intensity exercise * Self-collect urine before, after, and one-hour after exercise * Self-insert a rectal thermistor to measure core temperature * Complete cognitive tasks using the NIH toolbox before and after exercise to assess cognition * Complete the other condition (placebo or creatine) at least 21 days later

What is being tested

• Creatine Monohydrate (dietary supplement)
• Maltodextrin (Placebo) (dietary supplement)

Sponsor: University of Northern Iowa · Participants: 20 · Started: Mar 12, 2026

Contact the study team

• Assistant Professor, PhD · Phone: 5635137807

Official record on ClinicalTrials.gov — NCT07472426

Locations in the U.S.

Conditions

• Acute Kidney Injury
• Heat Illness

From ClinicalTrials.gov, data retrieved Sep 30, 2026. Each study sets its own eligibility; the study team decides who can join.