HOW MUCH PROTEIN DO YOU ACTUALLY NEED? THE NUMBER, NOT THE VIBE

"Eat more protein" is the most repeated piece of nutrition advice in any gym, and one of the least useful, because almost nobody follows it with a number.

More than what? More than yesterday? More than the person next to you?

If you are training four, five or six times a week, protein is not a vague suggestion. It is a number, it is knowable, and getting it right is the highest-return change most people doing Hybrid Training can make to how they recover and how quickly they progress.

This is part one of three. Here we work out your number. Part two covers what that number actually looks like on a plate, in real food. Part three deals with the bigger problem sitting underneath it — eating enough food overall.

Everything here is general guidance for healthy adults who train. It is not individual dietary advice, and the references at the bottom are there so you can check the source rather than take our word for it.

Start With The Number

For anyone training regularly with the goal of building or holding muscle, the working target is:

About 1.6 grams of protein per kilogram of bodyweight, per day.

That comes from a 2018 review in the British Journal of Sports Medicine which pooled 49 trials and 1,863 participants, and found that gains in muscle and strength kept improving as daily protein rose until roughly 1.62g per kg, where the curve flattened.

Two honest caveats. The confidence interval around that figure was wide — 1.03 to 2.20g per kg — so 1.6 is a sensible target, not a magic threshold. And it sits comfortably inside what the major sports nutrition bodies already recommend: the Academy of Nutrition and Dietetics, Dietitians of Canada and the American College of Sports Medicine put athletes at 1.2–2.0g per kg per day, and the International Society of Sports Nutrition at 1.4–2.0g per kg.

So 1.6 is not a fringe number. It is the middle of the mainstream range.

What that looks like in real bodyweights:

• 60kg — about 95g a day
• 70kg — about 112g a day
• 80kg — about 128g a day
• 90kg — about 144g a day
• 100kg — about 160g a day

One adjustment. If you are carrying a lot of body fat, run the maths off a realistic goal bodyweight rather than what the scales say this morning. Fat tissue does not need feeding with protein.

How That Compares With The New Zealand Guidelines

Here is where it gets interesting, and where a lot of gym advice gets it wrong in both directions.

The recommended dietary intake used in New Zealand is 64g a day for men aged 19–70 and 46g a day for women, rising to 81g and 57g after age 70. Those figures are built on reference body weights of 76kg and 62kg, which works out to roughly 0.84 and 0.75g per kg.

That number is a floor, not a target. It is the amount required to stop a sedentary adult developing a deficiency. It was never designed for someone squatting heavy on Monday, running intervals on Tuesday and back under the bar on Thursday.

But here is the part the supplement industry does not mention. National survey data shows New Zealand adults already comfortably clear it — median intakes are about 102g a day for men and 71g for women. Most Kiwis are not protein deficient, and Health New Zealand is quite direct that most physically active people do not need a protein supplement to meet their needs.

So this is not a deficiency story. It is a "the bar for hard training is higher than the bar for not getting sick" story. Those are different problems, and it is worth being clear about which one you actually have.

What Protein Is Actually Doing

Training is the signal. Protein is the material.

Every hard session creates small amounts of damage through muscle tissue. That damage is the point — it is the message that tells your body to come back stronger. But the rebuild only happens if the raw material is there.

Three other things protein quietly does:

• It keeps you full. Gram for gram it is the most satiating of the three macronutrients, which is why people who lift their protein usually find their snacking sorts itself out without any willpower involved.
• It protects muscle when you are losing weight. In a calorie deficit your body will happily break down muscle for energy. Adequate protein plus lifting is what makes it burn fat instead.
• It holds up as you age. This is why the New Zealand recommendation itself goes up after 70. Muscle is much easier to keep than to rebuild.

So What Is Your Actual Gap?

Take the national median and compare it to the training target. That is the honest size of the problem for most people:

• An 80kg man eating the national median of 102g is about 26g short of the 128g his training asks for.
• A 65kg woman eating the median of 71g is about 33g short of 104g.

That is roughly one decent meal's worth, every day. Not a crisis. Not nothing either — that gap, repeated across a training block, is the difference between adapting and just accumulating fatigue.

The Signs You Are Short

Under-eating protein while training hard tends to look like this:

• Soreness that lingers for three or four days when it used to clear overnight
• Strength numbers that have not moved in six weeks despite showing up
• Feeling hungry constantly, especially at night
• Losing weight on the scales but looking softer, not leaner
• Niggles that keep turning into proper injuries

None of that is proof on its own — poor sleep and simply doing too much cause the same picture, which is part three's territory. But in someone training hard, food is the first place worth looking, and you can rewrite the training week all you like without fixing a fork problem.

When You Need More Than 1.6

You are actively trying to lose fat. Go to 2.0–2.4g per kg. The ISSN goes further, suggesting 2.3–3.1g per kg for lean athletes in a genuine deficit. When energy is low, protein is what stops the weight you lose coming off your legs instead of your waist.

You are over about 50. Older muscle responds less to the same dose, so the same total works better spread into bigger hits — think 35–40g at each main meal rather than a token amount at breakfast.

You eat mostly or entirely plant-based. Plant proteins are generally less digestible and lower in leucine, the amino acid that switches the rebuild on, and most plant foods are missing one or more essential amino acids on their own. Aim roughly 10–20% higher, eat a wide variety of sources, and spread it across more meals.

You are in a very high volume block. Race prep, a heavy HYROX build, or a week where you have added running on top of everything else.

"You Can Only Absorb 30g At A Time"

This one will not die, and the evidence has moved.

The older guidance was that doses above about 40g did not add much. Then in 2023 a Maastricht University team fed 36 men either 0g, 25g or 100g of labelled protein after lifting and tracked it for 12 hours. The 100g dose produced a larger and much longer-lasting building response, with no ceiling detected, and less than 15% of the extra was burned off.

Spreading protein across three or four meals is still the better default, and every major guideline still recommends it — the ACSM position suggests roughly 0.3g per kg every three to five hours. But if your reality is a light breakfast and a big dinner, that dinner is not going down the drain. Hit the daily total first. Optimise the distribution second.

Is Too Much Dangerous?

Two things are true at once here, and you should hear both.

In healthy people, intakes in the 1.2–2.0g per kg range are what sports dietetics bodies actively recommend, and the "protein wrecks your kidneys" line comes from advice given to people who already have kidney disease, where it genuinely matters.

At the same time, New Zealand's own public health guidance is more cautious about going high, warning that excess protein adds surplus energy that gets stored as fat, may increase calcium losses over time, and gives the kidneys more waste to process. It also makes the point that everyday food costs less than supplements and brings zinc, iron and calcium along with it.

The sensible read: 1.6 is well within the recommended range for someone who trains. Chasing 3g per kg because a podcast said so is where you are paying more for less. And if you have kidney problems, are pregnant, or are managing any medical condition, talk to your GP or a New Zealand Registered Dietitian before making big changes.

Do This This Week

1. Work out your number. Bodyweight in kg times 1.6.
2. Track three honest days, including a weekend one. Do not change what you eat while you are measuring it.
3. Compare the two figures. If you land near the national median, you are probably 25–35g short.
4. Do not try to fix it all at once. Fix breakfast first, because that is almost always where the hole is.

Part two, next week, is the practical half — what that gap looks like in real food, using the New Zealand serving sizes, and how to close it without living on chicken and rice.

Fuel It Properly, Train Like You Mean It

If you have been training hard and the results have stalled, the answer is usually not a new programme. It is closing the gap between what you are asking your body to do and what you are giving it to do it with.

That is a coaching conversation as much as a training one, and it is one we have with members constantly. Our 21-day trial is $99 for three weeks of full access — strength, conditioning, and the recovery suite — with coaching from day one.

If you want the wider picture on eating around training, our earlier piece on eating for the session, not the mirror covers carbs and fats alongside protein.

Come and train with us. We will handle the standard. You handle the fork.

References

Where the numbers above come from, if you want to check them yourself.

• Health New Zealand | Te Whatu Ora. Eating and Activity Guidelines for New Zealand Adults (updated 2020).
• Health New Zealand | Te Whatu Ora. Behind the hype: High protein supplements (HealthEd NPA129, reviewed 2022) — source of the New Zealand RDI and median intake figures.
• Healthify He Puna Waiora. Proteins.
• New Zealand Nutrition Foundation. Protein.
• Morton RW, Murphy KT, McKellar SR, et al. A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. British Journal of Sports Medicine, 2018;52(6):376–384. PubMed.
• Thomas DT, Erdman KA, Burke LM. Position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and Athletic Performance. Journal of the Academy of Nutrition and Dietetics, 2016;116(3):501–528. PubMed.
• Jäger R, Kerksick CM, Campbell BI, et al. International Society of Sports Nutrition Position Stand: protein and exercise. Journal of the International Society of Sports Nutrition, 2017;14:20. DOI.
• Trommelen J, van Lieshout GAA, Nyakayiru J, et al. The anabolic response to protein ingestion during recovery from exercise has no upper limit in magnitude and duration in vivo in humans. Cell Reports Medicine, 2023;4(12). Full text.
• Dietitians Board of New Zealand — for checking that anyone giving you individual dietary advice is a New Zealand Registered Dietitian (NZRD).