A Primer on Protein Shakes


Today we’re going to go into some geeky detail about how to get enough protein, and where to get it from. 

I wrote a post last year about the basics of whole food protein, so if you're interested in that, most of it holds up still. 

Let’s talk about the king of supplements: the protein shake. 

What it is: 

Protein powders are a concentrated form of dietary protein used to supplement one’s protein intake for one purpose or another. They come from all sorts of sources: 

  • Milk
  • Soy
  • Rice
  • Egg
  • Beef
  • Hemp
  • Peas

And some other strange place like artichokes. It needs to have a high amount of protein when isolated and powdered. It’s common to find protein powders fortified with other vitamins, minerals, or performance enhancing agents (not to mention flavors). They are almost always highly processed and refined so they don’t spoil after an hour on the shelf. 

The idea is to have a fast, portable, and (lastly, apparently) tasty way to increase your protein intake.  

When to use protein shakes

The most common reason you’ll see people in the gym using protein shakes is to recover from their workouts and get protein in their system quickly post-WOD. Exercise, especially weight training, is about creating a stress and recovering from that stress. Protein intake needs to be adequate in order to experience the full benefits from a training program. 

For those in our 6-Week Challenge program, we use protein shakes as a way to increase protein intake without adding other non-protein calories from sugar or fat. That allows us to be precise with our short-term goal tracking. 

Some people will use a protein shake as a meal-replacement to minimize overall calories. This can work, but I usually don’t recommend it, as the meal satisfaction is usually low which I’ve found increases likelihood of falling off the wagon. 

Window of gains? 

Some people say that you need to chug protein immediately after you stop training in order to experience the most gains during the so-called “anabolic window” where muscle is most rapidly built. True or false? 


A review that looked at a collection of protein intake studies found that there was no correlation between protein timing and muscle growth within 4-6 hours post-workout. The clock doesn’t tick down  quickly before you turn into a scrawny pumpkin 30 minutes post workout. The most important factor for overall muscle building is the total daily protein intake. 

However, Just because it’s acceptable to wait before eating your post-workout protein doesn’t mean it’s optimal. Especially if you’re trying to maximize your performance in the gym or on the field. Those studies isolated protein intake and not overall post-workout nutrition.

Post-workout, you have a couple of things working in your favor. Your body will be looking to repair itself. Everything will be flowing faster, and it’ll be trying to grab raw materials. So by flooding the bloodstream with glucose and amino acids, we can make the repair process start faster and take advantage of some efficiency boosts from the training session. 

A great post-workout shake should be taken soon after exercise (wait until after you are cooled-down and your mobility work is done), and will include protein and carbohydrates. When we’re talking about CrossFit, we’re talking about glycogen (stored carbs) metabolism, which is most effectively replenished immediately after setting the weights down. 

In short: if you want to lose weight or stay optimally healthy, don’t sweat the post-workout shake if you don’t want to (better yet, just use BCAAs instead). If you want to breathe fire and get the most out of your training, shake it up fast. 

What’s the best protein? 

We evaluate protein “goodness” from a few factors. We want it to be protein-dense, low in carbs (we’d be adding those in ourselves if we wanted them for post-workout purposes), and easily available. 

Again, it seems taste is often forgotten. 

Generally, we digest and absorb a higher percentage of the protein in powders based on animal protein sources (whey, egg, beef, etc.) than we do from plant sources, but fortifications to the plant products often make them competitive. Beyond that, there are different methods of distilling the protein compounds from each source that make them more or less digestible or, mostly, expensive. Whey protein can be concentrated, isolated, hydrolyzed, or ionized, for example, and there are marginal differences to each process. If you’re going with whey,  

The main protein we carry right now at CFGE is rice-based. In my anecdotal experience, it has been just as effective as other powders, but it is really clean. I’ve never had issues digesting it, even on my worst days. At best you could describe my digestion as “fragile."

How much do I need? 

Most people training at the level we do need about .7g of protein per pound of bodyweight (140g/day for a 200lb person). That is total daily intake at the low level. For those of us trying to add muscle aggressively or improve performance, shoot for 1g per pound of bodyweight. If you’re sedentary (first of all, shame), shoot for at least .7g, and don’t do any supplemental carbs on top of your normal intake. 

Post workout, you want enough to jumpstart the process known as protein synthesis. This is your body working to take proteins and amino acids and put them to work, and it occurs when you’re recovering from training or when you consume a sufficient amount of protein. After a workout, start with about 20g protein for women, 30g for men to recover. If you’re in the camp that needs carbs as well, to hit a 2:1 ratio of carbs to protein (40g carbs, 20g protein for ladies, and 60:30 for guys).

Those recommendations are pretty standard across sports science when it comes to high intensity weight or anaerobic training sessions, or long aerobic sessions. If you don’t hit it that hard, peel back on the carbs. You have to earn them. 

Other concerns: 

A lot of proteins are created from some of the most common allergens: eggs, milk, soy, beef, etc. It’s one of the reasons we carry rice protein as our primary option. If you have a dairy allergy or are lactose intolerant, you still might be able to consume whey protein in a clean hydrolyzed or ionized form, as most of the lactose and other milk solids have been filtered out. Then again, you might not. 

If you’re looking for optimal health instead of peak performance, you may want to temper your shake-chugging a bit. Post-workout nutrition is great, and we can get a ton of “gainz” by taking advantage of the anabolic window. But after a high-intensity training session, you’re firmly in sympathetic nervous system response (fight-or-flight), which optimizes your body’s functions towards survival mechanisms. That means digestion is not going to be as smooth. That is mitigated by fast-digesting powders and sugars, but peak health might better be achieved by postponing the post-workout shake by 15-30 minutes when you’ve activated the parasympathetic (rest-and-digest) nervous system. Just something I’m playing around with. 

Hope you enjoyed your primer on all things protein. Thanks to Katie M. from CFGE for the question. 

If you have questions, ask away.

As a bonus, I’ve made this handy infographic for you to figure out where you might see the most benefit from today’s topic. 

Protein Shake Guide.jpg