Amino Acid
L-Isoleucine
Also known as: Isoleucine, Ile, BCAA
B
Evidence
Essential branched-chain amino acid (BCAA) important for muscle protein synthesis, energy production during exercise, and immune function.
Primary uses
- Muscle recovery
- Exercise performance
- Blood sugar regulation
- Hemoglobin synthesis
How it works
- Activates mTOR pathway for muscle protein synthesis
- Oxidized in muscle for energy during exercise
- Precursor for glucose during fasting
- Supports hemoglobin production
Dosage
- Typical range
- 3-6 g daily
- Timing
- Pre/during/post workout
- With food
- With or without
- Duration
- Safe long-term
- Special populations
- Athletes, those in caloric deficit
Forms
- Powder
- Capsule
Safety
Common side effects
- Well tolerated
Contraindications
- MSUD
- ALS (controversial)
Evidence notes
Well-studied as part of BCAAs for exercise performance
Grade B: Some human trials support key claims; further confirmation needed.
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