Is whey or collagen protein better for building muscle?

Read to the bottom of this post if you:

• lift heavy stuff because you want to build muscle
• are curious about or already are a vegan eater
• are an older athlete & want to hold on to your hard-earned muscle
• think you might be sensitive to whey
• like to stay lean

I know you’re here because you’re wondering what’s better for building muscle – whey or collagen protein?

We’ve known for a long time that animal proteins are superior for building muscle because they have a higher bioavailability (BV). This means that the amino acid profile in them is most closely matched to that of our human bodies, which means we use those proteins most effectively to repair and build muscle tissue (also called muscle protein synthesis, MPS).

You might’ve heard that whey protein (WP) is the best one for MPS, or maybe you’ve seen that whey is the kind that a lot of the athletes at your gym are using.

But collagen protein is also an animal based protein supplement (made from beef, pigs or fish), so hypothetically it should also give us superior MPS, right?

Not so fast…

It appears that the higher amount of a very special amino acid in whey protein – LEUCINE (which we’ve long known is the most important one for MPS), is what makes whey protein superior to any other for the athlete, and possibly even for older populations who are struggling to maintain their muscle mass.

WP has more LEUCINE than other protein supplements, including collagen, soy, and other plant-based protein powders.

“High-quality protein sources, such as milk-derived proteins casein and whey protein [WP]), are superior in stimulating muscle protein synthesis (MPS; Gorissen et al., 2016; Oikawa et al., 2020; Tang et al., 2009; Wilkinson et al., 2007) and increasing lean body mass (Aristizabal et al., 2015; Hartman et al., 2007; Volek et al., 2013) compared with lower quality proteins, such as soy, wheat, and collagen protein.

This is due to the essential amino acids that are required for MPS and that are in significantly larger amounts in animal proteins. One of these EAA in particular, LEUCINE, has been widely recognized as a direct stimulator of this process [mechanistic target of rapamycin (mTORC1; Blomstrand et al., 2006; Churchward-Venne et al., 2012, 2014; Jackman et al., 2017; Karlsson et al., 2004; Phillips et al., 2020), and is a key regulator of the translational machinery that stimulates MPS (Phillips et al., 2020; Wang & Proud, 2006)].”

But again, hold on…

There is such a thing as leucine supplements. Often derived from animal products, but also available in vegan-friendly (sourced from fermented lentils and other plant products), we could theorize that adding leucine supplement to a lesser leucine-containing protein may in fact, provide the same MPS benefits as whey.

And so alas, a recent study published in Int’l Journal of Sport Nutrition did just that.

They set out to investigate the effects of whey protein (WP) versus leucine-matched collagen protein (CP) supplement on muscle adaptations following a resistance training (RT) program in young adults.

Given that the alleged anabolic (aka muscle-building) superiority of WP has been mainly attributed to a higher leucine content (Devries et al., 2018a, 2018b), they hypothesized that leucine-matched CP supplementation would result in similar hypertrophic and functional gains compared with WP supplementation.

Their findings:

In contrast to their hypothesis, the results showed that WP supplementation (35 g, containing 3 g of leucine) was superior to leucine-matched CP supplementation (35 g, containing 1 g of leucine plus 2 g free leucine) to increase muscle size.

However, the study did not show that further gains in muscle performance (strength and power) during the RT program, when comparing the WP and leucine-matched CP supplementation groups.

These results match similar previous studies concluding the same findings for older women and older populations in general – greater muscle building gains, no difference in muscular strength or performance.

What do these results suggest?

Well, it’s pretty cool (for us nutrition nerds ????) because from a holistic approach, we know that nutrients work together in the body. It’s all those other co-factors, the different pieces of a large, complex puzzle that all come together to create the perfect environment for a particular outcome in the body.

Although we can support various outcomes with supplementation, like adding a little of this or that amino acid created in a lab – the more these things happen naturally together in whole foods or derivatives of, the more effective it’ll work in the body.

So… these results suggest that the formulation of supplements should consider the content of all EAAs (essential amino acids) – not just the really important leucine, but all those other amino acids that occur naturally together in various sources, like whey protein.

Here’s a takeaway from your question: Is whey or collagen protein better for building muscle?

• WHEY protein is superior for building muscle than any other protein powder supplement
• adding LEUCINE to lesser-quality proteins (like collagen or a plant-based) is an option, but won’t result in as great of gains
• the above might still be a viable option for the VEGAN builder

Note: all collagen protein (CP) supplementation studies report a positive effect on FAT-FREE mass (Jendricke et al., 2019; Kirmse et al., 2019; Oertzen-Hagemann et al., 2019; Zdzieblik et al., 2015). So if simply topping up your dietary protein & getting lean is your goal, collagen is a great choice! Remember though, that when it comes to muscle building gains, CP supplementation not only has a protein quality score much lower than WP, but also lower than both soy and rice protein (Phillips, 2017).

Oh… and on another note – not discussed in this study, but you might be wondering about egg white protein. It is a close second behind whey protein for MPS, due to its slightly lower amount of leucine.

For inquiring minds, this is the main source we used in this study recap:
Whey Protein Supplementation Is Superior to Leucine-Matched Collagen Peptides to Increase Muscle Thickness During a 10-Week Resistance Training Program in Untrained Young Adults in International Journal of Sport Nutrition and Exercise Metabolism, Jeferson L. Jacinto1, João P. Nunes2, Stefan H.M.