Isoleucine
The energy BCAA. Isoleucine is one of three branched-chain amino acids (BCAAs), along with leucine and valine. While leucine is king for muscle building, isoleucine excels at energy production and blood sugar regulation. It helps muscles take up glucose without needing insulin and serves as fuel during prolonged exercise.
Key Functions
Muscle Energy
Metabolized directly in muscle for fuel during exercise. Spares glycogen stores.
Blood Sugar Regulation
Stimulates glucose uptake into muscle cells independently of insulin. Helps stabilize blood sugar.
Hemoglobin Formation
Essential component of hemoglobin. Important for oxygen transport in blood.
Muscle Repair
Works with other BCAAs to repair muscle tissue after exercise. Supports recovery.
Immune Function
Supports immune cell function. May help maintain immunity during heavy training.
Wound Healing
Promotes tissue repair. Often depleted in trauma or surgery patients.
The Three BCAAs
The ideal ratio in supplements is typically 2:1:1 (leucine:isoleucine:valine), reflecting leucine's primacy for muscle.
Food Sources
Animal Sources
Eggs, chicken, beef, fish, dairy. All complete proteins contain good isoleucine.
Plant Sources
Soy, lentils, seaweed, spirulina. Combine grains + legumes for complete amino profile.