Clinical trial NCT06818253: Effect of Glycerol Hyperhydration on Running Economy of Long-distance Runners
Official title: Effects of Glycerol Hyperhydration on Running Economy in Long-Distance Runners
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Running
Physical Conditioning, Human
Keywords: Glycerol
athletic performance
sports nutritional sciences
thermoregulation
running
Lead sponsor: Iberoamerican Institute of Sports Science and Human Movement
Sponsor class: OTHER
Collaborators: name: University of Guadalajara
First posted: 2025-02-10
Enrollment: 30
Sex: ALL
Minimum age (years): 18
Maximum age (years): 35
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: TREATMENT

Brief summary: The aim of this study was to evaluate the effects of hyperhydration with glycerol on running economy (RE) in trained runners. The main questions sought to be answered are:

1. Does hyperhydration with glycerol improve running economy?
2. Are there beneficial effects on physical performance?

The researchers will conduct a clinical trial with 30 runners (15 men, 15 women) in three sessions. In the first session, VO2peak was determined and running speeds were established for sessions 2 and 3. In the second session, participants performed a stress test. In the second session, participants performed a running test in the euhydrated state under fluid restriction, and in the third session, with glycerol supplementation (22 ml/kg sports drink + 1.2 g/kg glycerol). Variables such as caloric cost unit (CCU), oxygen cost unit (OCU), heart rate (HR), body temperature (BT) and perceived exertion (RPE) were evaluated.


Eligibility criteria: Inclusion Criteria:

1. Competitive runners with a minimum record of 4.2 min/km.
2. Age between 18 and 35 years old
3. Apparently healthy athletes
4. Signature of informed consent form

Exclusion Criteria:

1. Presence of comorbidities that could alter the study variables (such as arterial hypertension, hyperthyroidism or heart disease).
2. Consumption of medications or stimulants (such as caffeine or diuretics) 48 hours before the tests.
3. Pregnancy.

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Primary outcomes:
measure: Maximal oxygen consumption (VO₂peak) (ml/kg/min)
timeFrame: In the first evaluation session to be held in the first week of a total of 3 weeks of study duration
measure: Running economy (CE)
timeFrame: In the first evaluation session to be held in the first week of a total of 3 weeks of study duration
Secondary outcomes:
measure: Body temperature
timeFrame: Body temperature was measured during sessions 2 (No Gly) and 3 (Gly) at the following times: at minute 0 (prior to the start of each test) and at minutes 5, 10 and 15 during a treadmill test.
measure: Perception of exertion
timeFrame: It was applied during the evaluation of the stress tests to determine the Vo2peak and Running Economy.
measure: Sweating rate.
timeFrame: In sessions 1 and 2, urine specific gravity (USG) was assessed, which was one of the key criteria for determining whether subjects could continue in the study without being eliminated.
Other outcomes:
Locations:
city: Guadalajara
country: Mexico
facility: Universidad de Guadalajara, Centro Universitario de Tonalá
state: Jalisco
Study officials:
References:
citation: Jolicoeur Desroches A, Naulleau C, Deshayes TA, Parent-Roberge H, Pancrate T, Goulet EDB. Effect of Glycerol-Induced Hyperhydration on a 5-kilometer Running Time-Trial Performance in the Heat in Recreationally Active Individuals. Nutrients. 2023 Jan 24;15(3):599. doi: 10.3390/nu15030599.