Best protein to build muscle
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Best Protein to Build Muscle: Insights from Recent Research
Introduction to Muscle Protein Synthesis and Protein Types
Muscle protein synthesis (MPS) is a critical process for muscle growth and repair, particularly following resistance exercise. Various protein sources, including whey, casein, soy, and protein blends, have been studied for their effectiveness in promoting MPS. This article synthesizes recent research to identify the best protein for building muscle.
Whey Protein: Rapid Digestibility and High Anabolic Potency
Whey Protein and Muscle Protein Synthesis
Whey protein is widely recognized for its rapid digestibility and high essential amino acid content, particularly leucine, which is crucial for stimulating MPS. Studies have shown that whey protein significantly increases amino acid uptake, mTORC1 signaling, and MPS in skeletal muscle3 4. Whey protein hydrolysate (WPH), a pre-digested form of whey, has been found to maintain elevated levels of phenylalanine utilization for synthesis longer than intact whey protein, indicating sustained MPS3.
Whey Protein in Older Adults
In older adults, supplementing breakfast with a vitamin D and leucine-enriched whey protein drink has been shown to enhance postprandial MPS and increase muscle mass over six weeks5. This suggests that whey protein is not only effective for young athletes but also beneficial for older populations aiming to preserve muscle mass.
Soy Protein: Comparable to Whey When Matched for Leucine
Soy vs. Whey Protein
There has been debate over the efficacy of plant-based proteins like soy compared to animal-based proteins like whey. A study comparing soy and whey protein supplements, matched for leucine content, found no significant differences in muscle growth and strength development following a 12-week resistance training program8. This indicates that when leucine content is controlled, soy protein can be as effective as whey protein in supporting muscle hypertrophy.
Protein Blends: Prolonged Amino Acid Delivery
Soy-Dairy Protein Blends
Protein blends that combine soy and dairy proteins may offer unique benefits by capitalizing on the properties of each protein type. Research has shown that a soy-dairy protein blend can prolong blood aminoacidemia and sustain elevated MPS longer than whey protein alone1. This prolonged effect is beneficial for maintaining muscle protein synthesis over extended periods post-exercise.
Collagen and Milk Protein Blends
A blend of collagen hydrolysate and milk protein has been found to stimulate MPS equivalently to a milk protein blend alone, despite having a lower essential amino acid content6. This suggests that protein blends can be formulated to optimize muscle anabolism effectively.
Optimal Protein Intake for Muscle Building
Per-Meal Protein Distribution
To maximize muscle anabolism, it is recommended to consume protein at a target intake of 0.4 g/kg/meal across at least four meals, reaching a minimum of 1.6 g/kg/day2. Higher protein doses (>20 g) may result in greater amino acid oxidation, but some of the additional amino acids are still utilized for tissue-building purposes.
Protein Supplementation in the Elderly
In frail elderly individuals, protein supplementation combined with resistance exercise has been shown to increase lean body mass and improve physical performance10. A protein intake of 1.5 g/kg/day has been found to be most effective in preventing sarcopenia and frailty compared to lower protein intakes7.
Conclusion
Whey protein, due to its rapid digestibility and high leucine content, remains a top choice for stimulating muscle protein synthesis. However, soy protein, when matched for leucine, can be equally effective. Protein blends, particularly those combining soy and dairy or collagen and milk proteins, offer prolonged amino acid delivery and sustained MPS. For optimal muscle building, a strategic distribution of protein intake throughout the day is recommended, with higher doses beneficial for older adults and those at risk of muscle loss.
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Most relevant research papers on this topic
Protein blend ingestion following resistance exercise promotes human muscle protein synthesis.
A soy-dairy protein blend effectively prolongs blood aminoacidemia, mTORC1 signaling, and protein synthesis in human skeletal muscle after resistance exercise.
RCT
Very Rigorous Journal
Highly CitedHow much protein can the body use in a single meal for muscle-building? Implications for daily protein distribution
To maximize muscle protein synthesis, consume 0.4 g/kg/meal of high-quality protein across four meals to optimize lean tissue accretion.
Literature ReviewVery Rigorous JournalHighly CitedWhey Protein Hydrolysate Increases Amino Acid Uptake, mTORC1 Signaling, and Protein Synthesis in Skeletal Muscle of Healthy Young Men in a Randomized Crossover Trial.
A small dose of whey protein hydrolysate effectively increases leucine transport into muscle, activates mTORC1, and stimulates muscle protein synthesis in young men, with anabolic potency and efficacy similar to intact whey protein.
RCTVery Rigorous JournalSupplemental protein in support of muscle mass and health: advantage whey.
Whey protein supplementation promotes muscle gains, maintains muscle mass during weight loss, and reduces muscle loss with age.
Literature ReviewHighly CitedSupplementing Breakfast with a Vitamin D and Leucine-Enriched Whey Protein Medical Nutrition Drink Enhances Postprandial Muscle Protein Synthesis and Muscle Mass in Healthy Older Men.
Supplementing breakfast with a vitamin D and leucine-enriched whey protein medical nutrition drink stimulates postprandial muscle protein synthesis and increases muscle mass in healthy older adults after 6 weeks.
RCTVery Rigorous JournalHighly CitedA collagen hydrolysate/milk protein-blend stimulates muscle anabolism equivalently to an isoenergetic milk protein-blend containing a greater quantity of essential amino acids in older men
A collagen hydrolysate/milk protein-blend stimulates muscle anabolism equivalently to an isoenergetic milk protein-blend containing a greater quantity of essential amino acids in older men.
RCTVery Rigorous JournalProtein supplementation improves muscle mass and physical performance in undernourished prefrail and frail elderly subjects: a randomized, double-blind, placebo-controlled trial.
1.5 g kg-1 d-1 of protein supplementation is most beneficial for preventing sarcopenia and frailty in prefrail or frail elderly subjects at risk of malnutrition.
RCTVery Rigorous JournalHighly CitedNo Significant Differences in Muscle Growth and Strength Development When Consuming Soy and Whey Protein Supplements Matched for Leucine Following a 12 Week Resistance Training Program in Men and Women: A Randomized Trial
Soy and whey protein supplements matched for leucine both support muscle growth and strength increases in untrained individuals after 12 weeks of resistance training.
RCT
Rigorous JournalThe Role of the Anabolic Properties of Plant- versus Animal-Based Protein Sources in Supporting Muscle Mass Maintenance: A Critical Review
Improving the amino acid composition of plant-based proteins through fortification, selective breeding, blending, and combining plant and animal-based protein sources can help maintain muscle mass in healthy individuals, especially in older individuals.
Literature ReviewVery Rigorous JournalHighly CitedProtein supplementation increases muscle mass gain during prolonged resistance-type exercise training in frail elderly people: a randomized, double-blind, placebo-controlled trial.
Prolonged resistance-type exercise training improves strength and physical performance in frail elderly people, but dietary protein supplementation is necessary for muscle mass gain.
RCTHighly Cited