I’d be rich if I was given money every time someone asked if they needed to drink a protein shake straight after a workout. Maybe I should ask for money each time.
Anyway, I can’t moan, because I always used to slam in a shake straight after my gym sessions. I’d always make sure to have a scoop of powder to bring to the gym.
I was doing this because I was trying to hit what is known as the anabolic window. It’s this time frame after a workout, where you had to drink your shake afterwards for it to be effective. The window is about 30 minutes. The idea was the sooner the better.
But was all this necessary?
All the evidence suggests it isn’t. This isn’t to say it’s a bad thing to do. But there is no need to slam in a protein shake after a workout. You’ll get little to no extra benefit.
Why protein shakes?
You may be wondering why protein shakes in the first place?
Are they magic?
No they’re not. They’re just a condensed form of protein.
Could you not just get all your protein from food?
Yes, you could. But people who regularly exercise need more protein than those that don’t.
The amount of protein needed for health is quite low. It’s 0.8g per kg of bodyweight. So if you’re an 80kg man that’s 64g a day.
The NHS England, says 50g is good for most people in general.
However, if you’re doing regular weight training you’ll need more. As you are using your muscles, they’ll need more than that to grow and repair.
Hence why it’s recommended to have 1.6g per kg of bodyweight, which is double. Therefore an 80g guy would need 128g a day. Split into 4-6 servings a day. So around 32g a meal or serving.
All the shake does is make hitting that target a lot easier. For some people relying on food alone can be tough. Not only tough it can be expensive, whereas powder is cheap. So long as you buy a good quality powder.
So as you can see shakes aren’t magic, they just make hitting your goals easier.
What happens if you don’t have a protein shake after a workout?
A few studies have been done on this to see what happens.
In 2017 a study was done to compare the effects of muscle growth on guys who drank a protein shake before a workout compare to guys who drank theirs after.
So one group drank a shake containing 25g of protein before their workout, the other group drank theirs after.
Both groups did 3 full body workouts per week, for 10 weeks.
When the study was finished, there weren’t any noticeable differences between the recovery or muscle growth between the 2 groups. (1)
“These findings refute the contention of a narrow post-exercise anabolic window to maximize the muscular response”
This study showed that consuming protein after a workout wasn’t essential. Therefore a few points could be made.
- The anabolic window may last hours after a workout instead of 30 mins
- The body will use protein in the same way if you eat/drink it before or after a workout
- Total daily protein matters more
When is the best time to have a protein shake after a workout?
As with most things in nutrition it depends. There isn’t really a best time.
But instead there’s some guidance which will serve 99% of people who are either looking to improve their strength, endurance or improve their physique.
Make sure to have a good serving of protein at least 4 hours after your workout.
Evidence shows after a workout the “anabolic window” lasts around about 4 hours not half an hour. (2)
This means after a workout your muscles will be primed to take in protein and use it to its best ability.
Does it have to be a shake?
No, any food containing protein will do just as good of a job. It’s advised that a meal or shake has at least 25g of protein, as that’s what’s needed to have an effect on your muscles.
If you want to be more precise 0.4g of protein per kg of bodyweight is the amount you want. Which for most people will be around 20-40g grams. (3)
There’s no need to be neurotic or super precise. Somewhere around that and you’ll be doing more than 99.9% of the work.
Does that mean eating or drinking protein after a workout is pointless?
If you’re slamming a shake in seconds after your workout for some magic effect, most likely yes it’s a waste of time.
You’d be fine to have your protein shake when you go home. Or yet still, have a normal meal with enough protein in.
But if you’re having a protein shake straight after a workout, as you won’t be eating for 4 hours afterwards, then that’s a good thing to do.
If you’ve always had a protein shake after your workout and it’s just become a habit, don’t stop because you’ve read this. Doing so won’t cause any harm whatsoever. For a lot of people, it’s a habit and it’s just part of your routine and makes you feel good. If that’s the case there’s no need to stop.
At the end of the day you should be training and exercising to make your life better and easier. Therefore I’m a big advocate of doing what makes your life easier. This should be enhancing your life, you shouldn’t be trying to make your life fit around meal timings and schedules.
You don’t need to have a protein shake after a workout. Getting adequate protein around 4 hours after will be fine.
Heck you don’t even need a protein shake, a meal or snack will do just as good a job.
You can even eat or drink your protein before your workout for it to have similar effects.
When it comes to protein please don’t overthink it. Just eat enough throughout the day and have 4-6 servings and you’ll be fine. If anything you might even be able to get away with 3 servings and still have most of the positive benefits if you wanted.
Who knows there may be evidence in the future saying that slamming a protein shake after a workout, does give an extra 1% benefit to elite athletes. But as for now, don’t worry about it.
Josh is a Registered Associate Nutritionist, with the Association for Nutrition (AFN). He completed his degree in Nutrition at the University of Roehampton in 2021. He passed with a First Class with Honours.
Josh is also a tutor for up-and-coming Personal Trainers, where he teaches a Level 4 Advanced Nutrition course. This is for Personal Trainers looking to upskill their nutrition knowledge. This is done at Norfolk Health & Fitness.