Research
Mixed
Ingesting glycerol, amino acids, or neurotransmitter precursors during exercise provides no benefit to athletes.
Do not waste money on glycerol, amino acids, or neurotransmitter precursors during exercise. They do not improve performance.
GoodRefutesHIGH confidence
Athletes do not benefit by ingesting glycerol, amino acids or alleged precursors of neurotransmitter.
Why this rating
Based on review of literature.
Source
Fluid and fuel intake during exercise
Edward F. Coyle · Journal of Sports Sciences · 2003
DOI 10.1080/0264041031000140545
narrative_reviewCited 406×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
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