Evidence supporting the use of: L-leucine
For the health condition: Muscle Tone (lack of)

Links: Go back one page, Tool main page, Ingredients list, Health conditions list, Body systems list

Synopsis

Source of validity: Scientific
Rating (out of 5): 4

L-leucine is an essential branched-chain amino acid (BCAA) that plays a critical role in muscle protein synthesis. Scientific research has consistently demonstrated that leucine acts as a key regulator in the initiation of muscle protein synthesis via the mTOR signaling pathway. Supplementation with leucine, either alone or as part of BCAA mixtures, has been shown to enhance muscle protein synthesis rates, particularly in situations where muscle tone or mass is compromised, such as aging (sarcopenia), immobilization, or certain chronic illnesses.

Clinical studies in both young and elderly populations indicate that leucine supplementation can help maintain or improve muscle mass and function, especially when combined with resistance exercise or adequate protein intake. For example, a 2017 review in Frontiers in Nutrition highlighted that leucine-enriched diets improve muscle protein synthesis and muscle mass in older adults. Furthermore, meta-analyses have reported modest but significant improvements in muscle strength and function with leucine or BCAA supplementation in individuals experiencing muscle wasting or weakness.

However, while leucine is effective in stimulating muscle protein synthesis, its benefits may be maximized when used in conjunction with other essential amino acids and physical activity. Overall, the scientific evidence supporting the use of leucine for improving or maintaining muscle tone is robust, though not absolute, earning it a high evidence rating of 4 out of 5.

More about l-leucine
More about Muscle Tone (lack of)

Products containing l-leucine

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
Designs For Health Detox Antiox™
Designs For Health Detoxification Support Packets
Designs For Health DHEA
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®
Designs For Health MyoStim™
Metagenics Perfect Protein® Pea & Rice Chocolate Powder
Metagenics Perfect Protein Pea & Rice Vanilla Powder
Metagenics Perfect Protein Whey Chocolate
Metagenics Perfect Protein Whey Vanilla
Designs For Health Red Yeast Rice
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
Designs For Health Vitamin D Supreme
Designs For Health Vitamin D Synergy