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High-throughput and Comprehensive Drug Surveillance Using Multisegment Injection-Capillary Electrophoresis-Mass Spectrometry
Published on: April 23, 2019
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β-Hydroxy β-Methyl Butyric Acid (HMB) and Its Potential Doping Relevance: A Pilot Study on Its Urinary Excretion
Cristian Camuto1, Xavier de la Torre1, Francesco Botrè1,2
1Laboratorio Antidoping FMSI, Rome, Italy.
Drug Testing and Analysis
|November 8, 2024
Summary
Beta-hydroxy beta-methyl butyric acid (HMB) supplements significantly increase urinary HMB levels above natural ranges for over 24 hours. This study confirms exogenous HMB intake is detectable, aiding sports supplement analysis.
Area of Science:
- Nutritional Biochemistry
- Exercise Physiology
- Analytical Chemistry
Background:
- Beta-hydroxy beta-methyl butyric acid (HMB) is a leucine metabolite found in sports supplements.
- HMB is marketed for its role in enhancing protein synthesis and sports performance.
Purpose of the Study:
- To investigate the urinary excretion profile of HMB after oral supplementation.
- To establish endogenous reference ranges for urinary HMB.
- To determine if exogenous HMB intake is detectable in urine.
Main Methods:
- Collected urine samples from 20 volunteers to establish endogenous HMB levels.
- Administered a 3-g oral dose of HMB to volunteers.
- Analyzed urine samples using gas chromatography-mass spectrometry (GC-MS) in selected ion monitoring (SIM) mode.
Main Results:
- Urinary HMB concentrations significantly exceeded endogenous ranges for at least 24 hours post-ingestion.
- The study demonstrated a clear distinction between endogenous and exogenous HMB levels.
- GC-MS in SIM mode proved effective for detecting exogenous HMB.
Conclusions:
- Exogenous HMB intake is readily detectable in urine for extended periods.
- This finding supports the use of urinary HMB analysis to verify supplement intake.
- Further research can explore HMB's efficacy and detection thresholds in athletes.
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