Adequate protein consumption is essential for muscle growth and maintenance. Those looking to see the full benefits of a weight lifting routine should aim to consume 1.0–1.5 grams of protein per pound of body weight.
Proteins are made up of amino acids, and they are the primary building blocks for new muscle growth. But not all protein is equal. Different types of protein, such as from dairy, red meat, fish, or plants, include different amino acids and they function differently in our bodies. To get the most from the protein in your diet and supplementation, it’s helpful to consider the differences between protein sources.
Bioavailability
Bioavailability refers to the body’s ability to absorb and make use of a nutrient. Certain forms of nutrients are easier for the body to digest and be put into use by your cells and tissues. This means that the form of protein you eat can affect the total percentage of the nutrient that your body is ultimately able to use.
Proteins also vary in terms of digestion time—that is how long it takes after consumption before your body is able to put the nutrient to use. This is helpful to consider so that you can fuel your body with the protein it needs to make repairs after a workout.
To meet ideal levels of protein consumption for muscle growth, most people will want to incorporate a variety of protein sources from supplements and whole foods.
Amino acids Amino acids are the building blocks that make up all proteins, but not all proteins are made from the same amino acids. We use 20 different amino acids to build proteins in our bodies. 9 of those are considered essential amino acids. These amino acids cannot be made by the body, so they must come from our diet.
In addition, some amino acids play a bigger role when it comes to muscle synthesis. Branch-chain amino acids (BCAAs) play an important role in muscle growth.
One way to account for differences in both bioavailability and amino acid richness is the Protein digestibility-corrected amino acid score (PDCAAS), which is used to rate protein sources. The table below rank some common protein sources based on their PDCAAS.
Protein Type and Protein Digestibility Corrected Amino Acid Score (PDCAAS)
Whey protein isolate
1.00
Casein
1.00
Egg
1.00
Milk
1.00
Beef
0.92
Black Beans
0.75
Pea protein
0.72
Peanuts
0.52
Wheat gluten
0.25
Adapted from: Protein – Which is Best? Jay R. Hoffman and Michael J. Falvo, Journal of Sports Science and Medicine 2004.
Fueling your workout
Ultimately, whey protein isolate is going to be the most bioavailable protein option. It’s also a rich source of BCAAs, making it especially beneficial for those looking to optimize muscle growth. Whey is one of the fastest digesting proteins, with amino acids available to your body in about an hour to an hour and a half. This makes whey protein isolate a fantastic option for fueling around workouts to optimize recovery and capitalize on muscle synthesis triggered by weight lifting.
Casein, on the other hand, shows evidence of having the best effect on protein synthesis over time. Casein is a slower-digesting protein, providing fuel for muscle repair over a longer period of time than whey protein. Muscle growth continues for 72 hrs after a strength training workout, so maintaining amino acid availability over a prolonged period is also important.
Because of these differences, some research points to the best results from protein supplementation that combines both whey and casein isolates. Making sure the rest of your diet is also based on whole foods rich in protein will also ensure you have a wide variety of protein sources.
Not just for muscle hypertrophy
Most of this conversation focused on muscle growth and strength building because of how fundamental protein consumption is to those goals, but adequate protein helps to support a range of goals. For those looking to drop their body fat percentage and slim down, fueling with enough protein will help the body maintain muscle mass through calorie restriction.
High protein diets are also helpful for those looking to lose weight. Protein keeps you feeling full and curbs your appetite, making them a great use of calories when you’re calorie restricting.
If you’re looking to optimize your diet and nutrition to support your weight lifting and body sculpting goals, Body By Ford personal trainers offer nutrition plans to support your fitness goals. Reach out to our team for more information or to set up a free consultation.
