L-isoleucine

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Other names for l-isoleucine

Branched-Chain Amino Acid (BCAA)
Free-Form L-Isoleucine
Isoleucine Powder

Synopsis of l-isoleucine

L-Isoleucine is an essential branched-chain amino acid (BCAA), meaning it must be obtained through the diet as the body cannot synthesize it. L-isoleucine plays a key role in muscle metabolism, immune function, energy production, and hemoglobin synthesis. It is one of the three BCAAs (along with leucine and valine) that are crucial for muscle protein synthesis, muscle recovery, and exercise performance.

L-isoleucine is known for its ability to promote muscle growth, repair muscle tissue, and increase endurance during exercise. It also plays a vital role in energy production, especially during periods of physical exertion, by helping to regulate blood sugar levels and providing fuel for muscles. L-isoleucine helps in the formation of hemoglobin, which is essential for oxygen transport in the blood.

L-isoleucine is found in protein-rich foods such as meat, fish, eggs, dairy, and legumes. It is also a popular ingredient in sports supplements, particularly those targeting muscle recovery, endurance, and exercise performance.

Historical Use
L-isoleucine, along with the other BCAAs, was first identified in the early 20th century as an essential amino acid required for protein synthesis and muscle metabolism. Historically, amino acids like L-isoleucine were recognized for their importance in muscle growth and tissue repair, particularly in populations with high protein needs such as athletes and bodybuilders.

In modern sports nutrition, L-isoleucine has become a staple in muscle-building formulas and pre- and post-workout supplements. It is also used in clinical settings to support wound healing and recovery from surgery or illness.

Modern Use
Today, L-isoleucine is most commonly used in sports nutrition and fitness supplements for its benefits related to muscle recovery, endurance, and fatigue reduction. Some of the most common uses of L-isoleucine include:

  • Muscle recovery: L-isoleucine is a key player in muscle protein synthesis, helping to repair muscle tissue after exercise and reduce muscle soreness.
  • Energy production: L-isoleucine contributes to blood sugar regulation and energy production during periods of physical exertion, helping to fuel muscles and improve endurance.
  • Endurance and performance: L-isoleucine, along with leucine and valine, plays an essential role in boosting exercise performance and delaying the onset of fatigue during prolonged exercise.
  • Immune function: L-isoleucine supports the immune system by aiding in the production of hemoglobin, which helps to transport oxygen in the blood and promote overall well-being.

L-isoleucine is available in capsules, tablets, powders, and BCAA blends, often used in combination with leucine and valine in sports supplements to improve exercise performance, muscle recovery, and fatigue reduction.

Safety Considerations
L-isoleucine is generally considered safe when consumed at appropriate levels through food or supplementation. High doses of BCAAs, however, may lead to gastrointestinal discomfort, including nausea, bloating, or diarrhea. It's important to consult a healthcare provider before starting L-isoleucine supplementation, particularly for those with kidney disease or individuals taking medications that could interact with amino acids. It is generally recommended to follow dosage guidelines to avoid potential side effects from excessive intake.

L-isoleucine is used for these health conditions

Athletic and Exercise Aids (Scientific)
Body Building (Scientific)
Muscle Tone (lack of) (Scientific)

l-isoleucine is used to support these body systems

Immune System (Scientific)
Muscles (Scientific)

Products containing l-isoleucine

Designs For Health Amino Acid Supreme™
Designs For Health Amino Acid Synergy
Thorne Amino Complex Berry
Thorne Amino Complex Lemon
Pure Encapsulations Amino-NR
Pure Encapsulations Amino Replete
Pure Encapsulations BCAA
Pure Encapsulations BCAA
Pure Encapsulations BCAA
Designs For Health BCAA Powder with L-Glutamine
Metagenics BCAAs Orange Mango
Metagenics BioPure Protein® Powder
Pure Encapsulations Essential Aminos
Douglas Laboratories Free Form Amino
Klean Athlete Klean BCAA + Peak ATP®
Klean Athlete Klean Essential Aminos + HMB®
Klean Athlete Klean Isolate ™
Douglas Laboratories Muscle Protect™ with HMB®
Metagenics Perfect Protein® Pea & Rice Chocolate Powder
Metagenics Perfect Protein Pea & Rice Vanilla Powder
Metagenics Perfect Protein Whey Chocolate
Metagenics Perfect Protein Whey Vanilla
Metagenics Ultra Glucose Control® Chocolate
Metagenics Ultra Glucose Control Chocolate
Metagenics Ultra Glucose Control Vanilla
Metagenics Ultra Glucose Control Vanilla
Metagenics UltraGI Replenish® Chocolate
Metagenics UltraGI Replenish Chocolate
Metagenics UltraGI Replenish Vanilla
Metagenics UltraGI Replenish Vanilla
Metagenics UltraInflamX Plus 360°® Chocolate/Orange
Metagenics UltraInflamX Plus 360° Mango
Metagenics UltraInflamX Plus 360° Mango
Metagenics UltraInflamX Plus 360° Orange
Metagenics UltraInflamX Plus 360° Original Spice
Metagenics UltraInflamX Plus 360° Pineapple/Banana
Metagenics UltraInflamX Plus 360° Pineapple/Banana
Metagenics UltraMeal Advanced Protein® Dutch Chocolate
Metagenics UltraMeal Advanced Protein French Vanilla
Metagenics UltraMeal Advanced Protein Plain
Metagenics UltraMeal Cardio 360°® Pea/Rice Chocolate
Metagenics UltraMeal Cardio 360° Pea/Rice Vanilla

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