2.5/5
Weak
evidence
Focus / nootropic evidence brief
L-tyrosine
May help cognition under acute stress or sleep loss, but direct gym-performance evidence is weak and recent sport trials are mostly unconvincing.
Headline Finding
Stress-cognition reviews are more supportive than sport trials; gym-performance evidence remains weak.
Dose Context
Most positive cognition work is stress-context specific; typical pre-workout dosing does not imply broad performance enhancement.
Important Caveat
Keep cognitive-stress claims separate from strength, endurance, and motivation claims in normal training conditions.
Source Drawer
Linked Research
- Review Stress/cognition review
- Trial Warm-environment exercise trial
- Trial Soccer performance RCT
- Review Military stress review
- Review Tyrosine cognition review
How To Read This Rating
The score reflects evidence that the supplement does its stated job. Some jobs are direct, such as strength, endurance, or recovery; others are indirect, such as sleep, mood, appetite, or health support. A real effect can still receive a cautious practical rating when dose, safety, product quality, or audience fit remain uncertain.
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