Physical Conditioning, Human, Running
Conditions
Keywords
Glycerol, athletic performance, sports nutritional sciences, thermoregulation, running
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.
Interventions
DIETARY_SUPPLEMENTThe Effect of Glycerol Supplements
The main factor that distinguishes this intervention is first of all the dosage of the dietary supplement and the effects on the variables to be analyzed related to physical performance.
Sponsors
University of Guadalajara
Iberoamerican Institute of Sports Science and Human Movement
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 35 Years
Healthy volunteers
Yes
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. \-
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Maximal oxygen consumption (VO₂peak) (ml/kg/min) | In the first evaluation session to be held in the first week of a total of 3 weeks of study duration | Session 1: VO2peak measurements through an incremental treadmill test with 2 km/h speed increments every 3 minutes, maintaining a constant 1% incline. The test started at 6 km/h for all participants and continued until volitional exhaustion |
| Running economy (CE) | In the first evaluation session to be held in the first week of a total of 3 weeks of study duration | Test under Hydration Restriction (No-GLY): As a mandatory requirement, participants reported to the laboratory in a euhydrated state (USG: 1.018-1.024) prior to the start of the test, following the criteria outlined in previous research \[31\]. They ran for 15 minutes on a treadmill at a speed equivalent to 65%-70% of their VO2peak from the first session. During the test, running economy variables such as the caloric cost unit (CCU), oxygen cost unit (OCU), body temperature (BT), rating of perceived exertion (RPE) via the Borg scale, and hydration status were measured. Running Economy Calculation: i) The caloric cost unit (CCU) was calculated via the following equation \[25\]: CCU =((VO2 x δ x 1000)/(V x MC)) x 100 where VO2 is the oxygen consumption rate (L/min); δ is the kcal/L of oxygen based on the respiratory exchange ratio (RER); V is the speed (m/min); and MC is the body mass (kg). |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Body temperature | 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. | The temperature will be measured during the running economy evaluation with an infrared thermometer (Berrcom® JXB-178). |
| Perception of exertion | It was applied during the evaluation of the stress tests to determine the Vo2peak and Running Economy. | The Borg effort perception scale, with a range of scores from 6 to 20, was used during the three sessions, recording the perception of effort in each minute of the test according to the following classification: * 6-7: Very very very light * 8-9: Very light * 10-11: Light * 12-13: Regular * 14-15: Heavy * 16-17: Very heavy * 18-19-20: Very very heavy |
| Sweating rate. | 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. | Fluctuations in body mass between the different sessions were evaluated. |
Countries
Mexico
Outcome results
None listed