top of page
  • Writer's pictureSophie Medlin

Protein for Exercise and Performance

Updated: Jun 15, 2022

How much protein do you really need when exercising? We break down the myths about supplements and talk about who really needs them.

Not many people know that one of my biggest professional and personal interests is in sports and exercise nutrition.

I am a bit(!) of an exercise junkie myself and I enjoy helping people to achieve their ideal body composition for their particular sport through optimal nutrition.

One of the things that comes up time and time again in the world of sports nutrition is protein supplementation. You can buy thousands of different protein supplements online in the most obscure flavours – peanut butter and jelly protein shake anyone?!

So what I thought I would do is sum up what we know about how much protein is needed for different exercise intensities, the best sources of protein, and optimum timing of protein intake.

How much protein do you need?

Well this depends on three important things. The first is your weight, because if you are bigger, you need more protein; the second is what activity you are doing; and the third is what you are trying to achieve.

For people who are exercising regularly, for more than an hour every day, you need 1-1.2 grams of protein, per kilogram, per day.

So if I weighed 10stone (for maths ease), that’s 63.5kg so I would need 63.5-76.2g of protein per day.

To give you an idea, a large chicken breast contains 64g of protein. So even if I am exercising for an hour every day, at 63.5kg one chicken breast would meet my needs. Do I need supplements? Nope.

If I decided that I wanted to be an endurance athlete and started training to run marathons (professionally), I might get some benefit from increasing my protein intake to 1.2-1.4g per kilogram per day. Based on my weight of 10stone, this works out to be 76.2-88.9g of protein per day.

So in addition to my large chicken breast, I might drink a glass of milk (10g protein) and eat an egg (8g protein) which would give me 82g of protein. Do I need protein supplements? NOPE.

If I decided that I wanted to be a body builder and get a massive booty and a chick pack (and maybe I do…) then we think that as a maximum – and this goes for everyone, not just women – as a MAXIMUM, we might use 1.7g of protein, per kilogram, per day.

That would be 108g of protein per day for someone who weighs 63.5kg.  

So I might have two eggs and a glass of milk at breakfast, tuna salad for lunch (17g protein in ½ tin), and chicken for dinner (plus some carbs and fruit and vegetables throughout the day). So, just eating like a normal human gives me 107g protein. EVEN FOR BODY BUILDING that is all you need. No more. No supplements needed.

Now obviously, I am talking about a 63.5kg person here. If you are already a large muscly man (and hi by the way…if you are) then you might weigh something more like 85 or 90kg. That is when the convenience of protein shakes plays a role.

If I was a 90kg male body builder and I decided that I needed 1.7g of protein per day to maintain my muscle mass, I would need 153g of protein per day. My protein intake would need to be something like:

Now, I know that men can eat a lot, but that is a lot of protein to try and eat in a day.

If you take the average protein supplement, you’re typically looking at 30g of protein per serving. So our friend in the example above could skip his morning milk (20g protein) and one of his eggs (8g) and enjoy the convenience of drinking his shake on the way into the office.

It is important to remember that there is no benefit to taking more than 2 grams of protein per kilo per day. You will just pee out the extra protein and that is literally money down the toilet. LITERALLY. We used to worry about too much protein being a strain on your kidneys too but unless you have a kidney problem it isn’t harmful, just wasteful and making your body work harder than it needs to.

Protein Sources

When we talk about sources of protein we need to consider the building blocks of proteins which are called amino acids. Every protein food has a different amino acid profile. For example, the protein found in meat, dairy, eggs and fish has a very different amino acid profile than the protein found in tofu, almonds and lentils. We all need plenty of the amino acids that we call ‘essential amino acids’ (these are sometimes called ‘branch chain amino acids’ BCAAs in the body building world), and foods from animal sources contain all of these essential amino acids. However, vegetarian and vegan sources are much more limited. I’m not being mean about vegetarian or vegan foods. It’s just a scientific fact.

Despite what the protein shake manufacturers will have you believe, the ideal amino acid profile can be provided by something that is available in almost every shop in the country - skimmed milk. Milk doesn’t have a website or a promo team (except for me) but it is cheap and doesn’t contain any weird ingredients, additives or flavourings, and it is THE MOST EFFECTIVE supplement’ for muscle recovery and growth.

And don’t even think about talking to me about how milk isn’t healthy because cave men didn’t drink it or because of hormones or anything else. Do you think cave men had protein shakes? DO YA?!

Whey protein is popular and is made from milk but has been played around and had additives crammed into it in the manufacturing process, so you actually lose some of the benefits of just drinking milk…and it will cost you twice as much.  

One thing to remember is that up to 50% of the world’s population are lactose intolerant, which means that they can’t digest milk properly and it causes stomach cramps and wind. When people take loads of protein supplements this often happens. If you think this applies to you, buy milk with the lactose predigested (Lactofree milk) or buy some lactase tablets which should solve the problem for you. If it doesn’t, I know a good dietitian so look me up.

Timing of Protein Intake

We do know that in order for muscles to recover and grow from exercise, we need to take some protein with some carbohydrate after exercise. Not as much protein as the salesmen would have you believe, but some. This also doesn’t need to be immediately after the exercise but within a couple of hours or so and the carbohydrate bit is really important to help us to use the protein effectively.

We also think that there is likely to be some benefit to having around 6g of protein before exercise. Again, skimmed milk has an ideal balance of carbohydrate and protein so if you drank half a pint on the way to the gym and half a pint on the way home, even for someone who is a big bodybuilder that would be ideal.


Calculate your protein needs from the table below:

And remember:

1. Don’t exceed 2g of protein per kilogram (I don’t care if you think you’re Arnie, this still applies to you)

2. THE OPTIMUM supplement is half a pint of milk before and half a pint of milk after training

3. And don’t forget, anyone with an agenda to sell you something will tell you that their product is the best. Milk doesn’t have a publicist and I’m not benefiting from telling you this… so why would I lie?

For information about clinics, appointments and services, please contact me.


bottom of page