If you pick up any fitness magazine these days, you’ll probably come across something on the importance of post-workout nutrition. Mainstream media has us believing that we need snacks (especially protein smoothies or protein bars) immediately after our workouts.
Is this really based on any scientific research or is this just what they call bro-science? Or maybe it’s something the protein supplement companies want us to believe?
I’ve spent the last few days looking through some of the latest research and reading what exercise specialists think. Contrary to what you’ve read or heard, based on the current evidence, most people don’t need an immediate post-workout protein shake/bar/snack 😮 . You can get all the nutrients you need from your next meal.
Whether or not you need to eat right after a workout depends on many factors and most of them don’t even apply to people who do moderate or light exercise. A blanket statement that everyone needs a post-workout protein smoothie or snack doesn’t make sense since there is no science to support that.
So should YOU be eating after your workout? Let’s dive in!
What’s the purpose of a post-workout (PW) snack?
Most trainers/nutritionists will recommend eating a post-workout snack that is a combination of carbs and protein. This combination of food is meant to do two things :
- Replenish the body’s energy stores.
- Repair and build muscles.
Let’s look at these two in a little more detail.
1. Replenishing the body’s energy stores: When you workout, you use the glycogen stored in your muscles as energy. Depending on how intense and how long the workout was, you could completely use up your muscle glycogen stores. (By the way, most people do not use up their entire glycogen stores during a workout – it takes a very intense workout to do that!)
If you happen to deplete your glycogen “stores”, you need to eat carbohydrates. Once the carbs you eat are used to replace the body’s glycogen, you’ll be ready for the next workout.
2. Repairing and rebuilding muscle: Workouts that include strength or resistance work can cause microscopic “tears”  in the muscles. In order to repair those tears and build muscle, the body needs amino acids. How does your body get amino acids? From the protein you eat.
So in order to keep your energy up and repair your muscles, your body will need both protein and carbohydrates after a workout.
Question is when and how should we get the protein and carbs we need?
Many trainers/sports specialists recommend a post-workout snack with both carbs and protein immediately after (or within an hour) a workout. it’s thought that our body absorbs nutrients for a limited time only, known as the “window of opportunity” and we need to make the most of it.
What’s the window of opportunity?
The “window of opportunity” refers to a short time period (less than an hour) after a resistance workout where your muscles are primed for growth as long as you eat enough protein.
So basically this theory says that we need to eat quickly after a workout, otherwise we aren’t getting optimal muscle growth. Is this actually true? Not really.
Recent research shows that as long as your body gets enough protein and carbs within a couple hours after a workout and throughout the day, you’re good. It doesn’t have to be something you do as soon as your dumbbells hit the ground!
In a well-controlled study published in 2012 , researchers studied healthy men (23 years old) who worked out for 12 weeks. One group consumed 20g of protein immediately post-workout and the other group ate a placebo. Also, the study participants were told to drink only water in the 2 hours before and 1.5 hours after each training session.
So what did they find after twelve weeks? They found was that the muscle size and strength gains following exercise were identical for both groups. Identical! Consuming protein immediately after a workout did not offer any benefit. The study was small, so I wanted to dig a little deeper.
In a paper published in 2013 , top researchers in the field of sports nutrition, Alan Aragon and Brad Schoenfeld, reviewed the existing scientific literature on the “window of opportunity”. What did they find? They found that there’s no definitive evidence that consuming protein immediately after a workout was necessary. They do suggest that post-workout nutrition is important, it’s just that it doesn’t have to be immediately after you finish your workout. You can wait a few hours if you need to.
In late 2013, a meta-analysis was published that came to a similar conclusion . The authors found that protein timing was not critical for muscle development.
So what does all this mean? Protein timing isn’t as important as we thought. While the timing isn’t that important, eating sufficient protein is still very important . You may not need a protein shake/bar immediately after your workout, but make sure you get enough protein in your meals later that day.
Based on the current science, there is no conclusive evidence for eating immediately after a workout. You’ve definitely got some time to eat.
So why are we still told to eat right after a workout? I don’t know for sure, but I guess it probably has a lot to do with the protein powder/supplement/bar companies that have a product to sell. Don’t you think so? They wouldn’t be able to sell you anything if you knew that you had time to drive home and dig into dinner two hours later 😉 .
So what does this mean for you?
Are you an athlete or do you do really intense or glycogen-depleting workouts?
If you’re an athlete who trains multiple times a day or are into intense body-building or other demanding workouts, then your body has different requirements from the majority of people. You probably need a post-workout snack. But does it have to be the minute you’re out of the gym? Nope, but it would be useful to eat something soon. Why so?
For an athlete, a post-workout snack (one that includes carbs) within as short period of time seems to be a great way to to restore the body’s glycogen stores as soon as possible , so your muscles can be ready for the next workout. Eating carbs even a few hours after a workout is not as effective as eating them immediately when it comes to replenishing glycogen quickly . For non-athletes, replenishing glycogen fast is not that important unless you’re working out multiple times a day.
Are you a non-athlete? Are you a moderate or light exerciser? Are you trying to lose weight?
For you, post-workout snacks are NOT a must. Basically, you don’t have to eat immediately after a workout if you don’t feel like it. And if you’re trying to lose weight, you don’t need the extra calories of a protein shake!
However, if you’re hungry, go for it. Don’t starve yourself. But if you’re not hungry, you can safely wait for your next meal (breakfast, lunch or dinner) to get your protein and carbs.
The only time you absolutely need a post-workout meal is if the following scenarios apply to you:
- if you’re working out again on the same day. Then you’ll need to replenish your muscle glycogen quickly for the next workout .
- if you worked out in a fasted state (e.g. working out first thing in the morning on an empty stomach). In this case, you really should eat to prevent your body from breaking down muscle .
- if you won’t be eating a meal in the next couple hours. If you’re not planning on eating a meal in the next couple hours, then it makes sense to have a post-workout snack so your body can get some of the nutrients it needs.
Other than that, you don’t really HAVE to eat a snack after your workout as long as you’re eating adequate protein and carbs throughout the day from your meals.
Do what you feel like and what works for your body. Don’t do something because you feel like you need to, especially since the science doesn’t back up the need for an immediate post-workout snack.
The point I would really like to highlight here is that there’s really no need for pressure to eat those protein bars or down a protein smoothie after a workout.
Just remember that for the majority of us who aren’t endurance athletes and don’t do intense workouts, a post-workout shake or bar isn’t essential. Eat balanced meals and get your protein and carbs from real foods, not pricey supplements that probably won’t help you with your specific goals.
TAKE HOME MESSAGE
- There’s no concrete scientific proof that eating a post-workout snack immediately after a workout is necessary. You’ve got a couple hours to eat.
- If you’re an athlete or extreme body-builder or someone who trains many times a day, a post-workout snack is a good choice.
- For everyone else, a post-workout snack is NOT essential.
Let us know what you think! Leave a comment below after the “other posts” section.