And you're definitely not the only one at the gym using a protein supplement.

In 2017, 9.4 billion dollars was spent on whey protein globally.

So is protein powder actually helping you build muscle, or are you turning your money into dust?

Let's talk about how your body uses protein to build muscle and whether protein shakes are helping you get the best out of resistance training.

Welcome to DocUnlock, where we help you make better decisions about your health.

So how exactly does your body build muscle?

When it comes to increasing the size of any organ, the body only has two options:

You can either increase the number of cells, called hyperplasia, or you can make each cell bigger, called hypertrophy.

When it comes to building up new muscle, your body can't build new muscle cells, so your body relies on muscle hypertrophy.

So how does muscle hypertrophy work?

If you look at a muscle cell under a microscope, what you will see are long tubes of fibres running along the length of the cells.

These are called myofibrils and are full of protein-based fibres.

When a muscle cell builds more of these protein fibres, it gets bigger and stronger.

To achieve muscle hypertrophy there's a simple rule, Muscle Protein Synthesis (MPS) needs to outweigh Muscle Protein Breakdown (MPB).

And to trigger Muscle Protein Synthesis, you need 2 ingredients: resistance training and protein from your diet.

If your body doesn't get enough protein from your diet, then it can't trigger muscle protein synthesis effectively.

And this is where the advice comes from to include protein in your diet especially if you're doing a lot of resistance training.

Most people living in high income countries get enough protein from their diet for normal body function.

But we know that protein needs are higher in those people who are deliberately trying to achieve muscle hypertrophy.

But does adding protein powder to your diet help you get better results from resistance training?

Well, there have been so many studies done on the topic!

If only there was a meta-analysis that put all the results together so that we can get the best answer possible.

Ah HAH! Found it!

Published in 2017 in the British Journal of Sports Medicine, this is the largest review so far on whether protein supplementation leads to gains in muscle mass and strength.

It combined the results of 49 randomised controlled trials.

In these trials, almost 2000 people were put on a resistance training program.

In these people, the average protein intake even before supplementation was approximately 1.4 grams of protein per kilogram, per day,

and this is already above the recommended dietary allowance of 0.8 grams per kilogram, per day.

The experimental group received an additional protein supplement of 36 gram per day on average, with almost half of the trials using whey protein.

The control group most commonly received a carbohydrate supplement to make sure that the total calories were the same as the experimental group.

The average resistance program was 13 weeks long, with training sessions 3 times per week.

On average, each session had 7 exercises, 4 sets per exercise and 9 reps per set. And the results?

Well, protein supplementation improved strength, muscle size and lean body mass.

So you aren't wasting your money after all, protein supplementation does lead to some benefit.

BUT WAIT – there's a catch.

First, there is a point where adding more protein doesn't lead to more benefit.

The researchers found that the benefit of protein supplementation plateaued after a total daily intake of 1.6 grams of protein per kilo, per day.

For someone weighing 70 kilos, that would mean a total protein intake, both from food and supplements, of 112 grams per day.

And the second thing: even though protein supplementation did have a benefit, it's not as impressive as you might think.

When it came to improvement in strength, participants who didn't use a protein supplement increased their 1 rep max by an average of 27 kilos just through resistance training alone.

Those who were given a protein supplement had an additional benefit of 2.49 kilos.

In other words, protein supplementation contributed an additional benefit of only 9%.

What does this mean?

Well, the researchers tell the story best:

"The practice of Resistance Exercise Training is a far more potent stimulus for increasing muscle strength than the addition of dietary protein supplementation."

If you're a professional athlete where every last bit of strength counts, then yes absolutely optimise your protein intake.

For serious athletes, this study recommends supplementing protein intake to an upper limit of 2.2 grams per kilo, per day, to get the maximum possible benefit from protein supplementation.

But if you're an average person like me just trying to stay fit, then protein shakes will help you a bit, but not as much as getting to the gym and actually doing the work.

So the next time you see someone at the gym drinking some protein, the real question is: "Hey bro, do you even lift?"

In this video I've only looked at the effect of protein supplementation on strength training.

There are some other reasons why people use protein shakes:

to boost protein intake without eating a lot more calories, to suppress appetite or to aid in recovery after cardio.

If you're interested in these topics, drop a comment below.

And if you're interested in getting specific advice about your particular situation and protein intake, then I would suggest seeing a sports dietician.

A common concern about a high protein diet is whether there are any negative effects on your health.

For example, could a high protein diet cause lead to worse acne, hair loss or even cause kidney damage?

In the next episode, I'm going to look at the science behind these questions.

So make sure you're subscribed for that and the video will be up there to your right when it's released.

Thanks for watching and I'll see you in the next one.