How Important is That Post Work-out Snack Anyway?

Just how important is that post workout snack? Is it necessary to eat it right after my workout, even before I shower? This post will cover some of the scientific research regarding the timing, macronutrient composition, and importance of having a post workout (recovery) snack. I’ll also give you some tips on what you should do, based on your fitness and performance goals.

What evidence shows is that during and following a workout:

• Our bodies crank up the number of available amino acid transporters (little taxis for small pieces of protein), secondly,
• insulin sensitivity is also increased, so muscles take in sugar and fat from the blood stream more readily, and finally,
• a larger presence of circulating anabolic (muscle building) hormones occurs. 

Thus we have an environment favoring protein accretion and presumably muscle growth. We can refer to this time period following a workout to the “window of opportunity”.

Ingesting dietary protein at this time is optimal as our bodies will preferably utilize what we just ate. This is better than trying to find the necessary amino acids elsewhere (free AA pool or “storage”). Taking from “storage” is not ideal because it requires breaking down lean tissue (muscle) to get at the amino acids. There is no consensus on exactly how much protein (the supplier of amino acids) is optimal. Literature suggests, following a resistance training workout .25g/kg bodyweight might work the best. For example, a 70 kg (154 lbs) person would need 17-18 g of protein in their post workout snack. The handy-dandy chart below estimates the grams of protein for a post workout snack for various bodyweights.

Another important post workout macronutrient to consider..

Of course, protein is NOT as important as replenishing muscle glycogen (stored sugar, used by muscles), making carbohydrates an important consideration in the post workout recovery snack. The literature, again, varies but generally 1-2g/kg bodyweight of carbohydrates as soon as possible following the workout (any type of workout, not just resistance training) appears to be optimal. Additionally, ingesting carbohydrates with protein appears to aid with amino acid absorption. Ideal carbohydrate to protein ratio in a post workout snack is 3-4:1. So, our 70 kg (154 lbs) example from above would want their 17g of protein complimented with ~60g of carbohydrates. Done deal right? Not so fast…

The other side of the post workout snack argument

Evidence also shows us this “window”, the hour following the workout, gradually closes, remaining open to some degree up to six hours; In some cases it remains open, though not as “wide”, up to 24 hours. Furthermore, those who fail to eat during the 1 hour “window” of opportunity yet consume enough calories to support their needs over a 24 hour period make similar gains in muscle mass and performance compared to those who consume the recommended snack during the “window” following their workout.

What does all this mean?

Of course more work needs to be done to determine exactly what we ought to be doing. Likely what we’ll find is some athletes, elite athletes perhaps, who pay close attention to nutrient timing will indeed gain that extra fraction of a benefit that is important at their level. The rest of us probably won’t suffer performance decrements so long as we are getting the right foods in the right amounts over the long run. There is more to this picture, as the “speed” of absorption of the protein matters, the “quality” matters as well. I will talk more on these in a future post. For now, the main messages are as follows:

For elite athletes or those who train more than once per day:

Have a snack immediately following your training session. It should consist of carbohydrates at 1g/kg bodyweight, and high-quality fast-digesting protein (whey is a good example) equal to .25g/kg bodyweight. Repeat in another hour. This should be adequate to replenish muscle glycogen and fulfill protein needs. Which will be necessary for performing the second training session.

For those who are trying to lose weight, or do not train multiple times per day:

Nutrient timing is not as important. Eat a regularly scheduled meal, such as lunch or dinner within a couple hours of the workout. A normal meal, such as a turkey sub, salad, and juice will cover your workout recovery needs just fine. Your goal is to make sure that you are getting the calories you need over the whole day.

For those trying to gain muscle mass:

Its probably a good idea to have a post workout snack, BUT adjust the rest of your meals accordingly. To gain muscle mass, an additional 300 kcal per day is all you’ll need. More than that and the extra mass gain will likely be fat, not muscle.

If you’re not sure which of the above best applies in your situation, ask yourself these questions:

• Is your bodyweight where it should be?
• Are you training for at least 90 minutes on a given day (in one or more bouts)?

If the answer is yes to both, then perhaps the first option is suitable. If the answer is no to either or both of those, then the second or third option is likely appropriate. Hope this is helpful. If this article led you to make a change in how you approach your post workout recovery eating, please leave a note below and let us know what you are doing now.

Consequently, if you are interested in reading more about this topic, you may enjoy "Do We Really Need More Protein?".

Thanks and enjoy!

Ready to make a change in your diet/eating habits? Better yet, ready to improve your life? Check out my remote, holistic, Nutrition Coaching program!

Published by mattktraining

I am currently the Owner of my soloprenuerial company Matt K Training. Through my fitness and nutrition programs I help adults develop skills and practices that help them eat, move, and recover well. Over the past 20 years, in various roles such as a Personal trainer, Exercise Physiologist, Clinical Researcher, and Health Coach I have helped hundreds of adults reach their health and physical performance goals. When not working, I enjoy active pursuits such as playing right field for the Charlton Giants (in a 38+ competitive baseball league), playing tennis, hiking, backpacking, and rock climbing. I also enjoy indoor activities such as playing strategy board games, reading and discussing science fiction literature, dabbling with my guitar, finding creative ways to eat oatmeal, and being a good dad.