How much protein do you need if you train?

Tick “I do strength or endurance training regularly” in the protein calculator and a second result appears under the recommended intake, labeled “If you train”. At a body weight of 70 kg it reads 84–140 g. That is a gap of 56 g between the two ends, so it helps to know where the range comes from and how to read it.

Who came up with 1.2–2.0 g?

The figures come from a joint position statement published in 2016, “Nutrition and Athletic Performance”. Three organizations issued it together: the American College of Sports Medicine (ACSM), the Academy of Nutrition and Dietetics, and Dietitians of Canada. It is written for active adults and competitive athletes. It says the protein needed to support the body’s adaptation to training, recovery and the rebuilding of tissue generally falls between 1.2 and 2.0 g per kg of body weight a day.

It answers a different question from the recommended intake

The recommended intake at the top of the calculator comes from that country’s dietary reference values. The “If you train” range comes from the same joint statement on every country’s page. The two are answers to different questions.

	Recommended intake	If you train
Set by	Each country’s dietary reference values	A joint statement from three sports nutrition bodies
The question	How much do you need to avoid falling short?	How much do you need to support the gains from training and recovery?
Form	A single value	A range
What the calculator needs	Sex and age	Weight and the training checkbox

The statement explains that traditional requirement studies set out to find the amount that prevents deficiency, mostly in people who sit for most of the day, and that athletes do not fit those conditions. On that basis it sees good reason to advise intakes well above the recommended intake.

How the calculator works it out

It multiplies the weight you enter by 1.2 and by 2.0, then rounds each result to a whole gram.

Weight	Lower end (× 1.2)	Upper end (× 2.0)	Shown on screen
58 kg	69.6 → 70 g	116 g	70–116 g
70 kg	84 g	140 g	84–140 g
82 kg	98.4 → 98 g	164 g	98–164 g

The range appears only when all of the following are true.

• You have ticked the training checkbox.
• You have entered your weight. Leave it blank and “Good to know” asks you to enter it.
• Your age falls in the adult band of that standard.
• You have not selected pregnancy or breastfeeding. If you have, a note telling you to talk to your doctor appears instead of the range.

Where you sit within the range

The statement no longer recommends the older approach of giving strength athletes one fixed target and endurance athletes another. It treats your need as something that moves within the range as your training changes.

• People with long training experience need less.
• When you step up how often or how hard you train, or start something your body is not used to, you are nearer the upper end.
• If you are eating less to lose weight, or an injury has suddenly stopped you training, 2.0 g or more may help prevent the loss of fat-free mass (muscle and other tissue that is not fat).
• Enough energy comes first. If you are short on calories, and on carbohydrate in particular, protein gets burned for energy.

The statement puts as much weight on spreading protein through the day as on the daily total. The amount it suggests for one sitting is 0.25–0.3 g per kg of body weight, eaten within 2 hours after exercise and then again every 3–5 hours. At 70 kg that is 17.5–21 g at a time. Four servings of 21 g add up to 84 g, the same as the lower end of the 70 kg row in the table above. According to the statement, there is no evidence yet that eating more than 40 g in one sitting raises muscle protein synthesis any further.

What the range does not tell you

• It does not mean more is better. The upper end is not an upper limit. It is the far edge of the band where most needs fall.
• It does not mean you need supplements. The statement says intakes at this level can generally be met from food.
• It is not a standard for anyone who is pregnant or breastfeeding, or who is not yet an adult. The calculator does not show the range in those cases.
• It may not be right for people with kidney or liver disease. That is why a note about talking to your doctor always appears under the result.

The statement itself treats these figures as general guidance and advises working out a personal plan with a qualified dietitian. The calculator’s numbers are for reference and do not replace professional advice.