Maintaining a svelte and cut physique has become a fitness ideal. According to the experts, people with less body fat and increased lean muscle mass experience plenty of health benefits. In addition to burning calories more efficiently, muscle mass derived from strength training can improve bone health, help manage weight, prevent complications from chronic medical conditions, improve cognition, and enhance quality of life.
Strength training, however, is only one side of the coin. We are, after all, what we eat. Numerous studies have found that protein supplementation can facilitate muscle building when combined with regular strength training.
Indeed, high-quality proteins are inherent in the quest to become more muscular.
“It is important to preserve skeletal muscle mass to maintain or improve metabolic homeostasis and physical function. In this context, the rates of protein synthesis and degradation in skeletal muscle constantly adapt in order to maintain muscle mass,” wrote the authors of a review published in Nutrients.
Physical activity and food intake both play a major role in muscle protein synthesis and muscle protein breakdown rates, noted the authors. “In healthy adults, dietary intake is generally associated with an increase in the plasma concentrations of nutrients and hormones causing an increase in protein synthesis and a decrease in protein breakdown rates, in particular in skeletal muscle.”
Here's a closer look at five protein sources that help build muscles.
Despite an emerging corpus of research proving otherwise, some people are wary of eggs over concern that they are high in cholesterol. In reality, there’s a paucity of research correlation between egg intake and heart disease and, in fact, at least six clinically proven reasons why eggs are actually beneficial for heart health.
Eggs are considered the gold-standard protein source, and with good reason—their nutrition profile is off the charts. One large egg contains 75 kcal, 6 g of protein, and only 1.5 g of saturated fat. And an egg white has 16 kcal, 3.5 g of protein, and 0 g of fat.
Eggs are also considered a functional food, which means that they provide health benefits beyond nutrition, such as improved immune functioning.
In its most recent position statement, the International Society of Sports Nutrition lauds eggs.
“Egg protein may be particularly important for athletes, as this protein source has been demonstrated to significantly increase protein synthesis of both skeletal muscle and plasma proteins after resistance exercise at both 20 and 40 g doses. Leucine oxidation rates were found to increase following the 40 g dose, suggesting that this amount exceeds an optimal dose. In addition to providing a cost-effective, high-quality source of protein-rich in leucine (0.5 g of leucine per serving), eggs have also been identified as a functional food,” they wrote.
In the aggregate, eggs are easy to digest and prepare, thus making them perfect to help build muscle. They can be eaten alone or combined with breakfast, lunch, or dinner. Click here for a nutritionist’s take on the benefits of eggs.
The protein derived from meat contains the full complement of essential amino acids in proportions similar to that of human skeletal muscle. A 30 g serving of beef, for example, stimulates protein synthesis in young and older people alike. Meat is also rich in micronutrients, including selenium, iron, vitamins A, B12, and folic acid. This combination of minerals and micronutrients is hard to obtain from plant-based proteins.
According to the aforementioned position statement, “Research has shown that significant differences in skeletal muscle mass and body composition between older men who resistance train and either consume meat-based or lacto-ovovegetarian diet.”
They added, “These results indicate that not only do meat-based diets increase fat-free mass, but also they may specifically increase muscle mass, thus supporting the many benefits of meat-based diets. A diet high in meat protein in older adults may provide an important resource in reducing the risk of sarcopenia.”
Important proteins found in dairy products include whey and casein. These proteins provide amino acids necessary to build muscle.
According to the authors of the aforementioned Nature review, milk proteins outperform plant proteins in their ability to generate muscle. The authors cited a study that demonstrated that in young men who performed resistance exercise, drinking skim milk yielded a 43% higher muscle protein synthesis rate than in those who drank an isonitrogenous/isocaloric soy protein isolate.
In other cited research, the authors noted that the muscle protein synthesis rates were 30%-40% lower in older adults consuming soy or wheat protein hydrolysates vs whey protein isolates or micellar casein.
“These differences might be related to protein digestion rates, which are faster for soy and whey proteins than for casein,” the authors wrote.
Cereals plus legumes
Cereals and legumes harbor complementary protein profiles, noted the Nature review authors. Specifically, proteins lack lysine, and legumes lack sulfur amino acids but eaten together, they can help the body meet essential amino acid requirements.
“[M]ixing different plant-based proteins could compensate for the lower anabolic capacity of these protein sources, which means that combining various plant-based protein sources like cereals and legumes in the same food could improve essential amino acids composition to help meet the body’s needs and even prove more efficient than fortification with free limiting amino acids,” they wrote. “The free essential amino acids used to fortify plant-based proteins could be digested and absorbed faster than their constitutive amino acids.”
From a manufacturing perspective, the authors suggested fortifying cereal products with legumes. Such processing could enhance essential amino acid compositions and facilitate better body protein retention, although more research on the topic needs to be done.
For more information on the benefits of legumes, click here.
Plant plus animal proteins
The whey component of milk is considered a high-quality protein. But, the authors of the Nutrients review noted that studies showed mixing milk and soy resulted in similar levels of protein synthesis compared with that of consuming whey protein alone. Furthermore, net muscle protein synthesis/degradation and protein balance were also similar, as well as the activation of the signaling pathways driving the protein translation rate and net protein balance.
“Regardless of age, these studies show that combining plant [proteins] with animal proteins can activate muscle protein anabolism in a similar way to high-nutritional quality proteins, such as milk proteins,” the authors wrote.
If you’re looking to build muscles, animal proteins, such as those found in eggs, meat, and dairy, are likely your best bets. Nevertheless, proteins found in legumes and cereals can also do the trick—especially if combined. Remember that to build protein, resistance training must be combined with high-quality proteins.
All things considered, for those intent on transforming their physique, it may pay to solicit input from both a nutritionist and a physical trainer.
To learn more about protein alternatives to red meat, click here.