Resources
Protein requirements for endurance sports training
On this page:
The importance of protein for endurance athletes
What the science says about the right amount of protein
A quick way to calculate protein requirements for meals and snacks
This image was generated by AI. Sorry it’s slightly terrifying. The illustrated portion size is not a recommendation.
The importance of protein for endurance athletes
There is a persistent myth that protein supplementation is for bodybuilding or strength athletes but not endurance athletes like runners and triathletes. It’s completely wrong. In fact, protein is vital for endurance training. Carbs provide the fuel, but only protein will enable muscles to regrow and get stronger.
And no, protein does not lead to bulk. Professional triathletes and cyclists will consume similar quantities of protein daily to competitive body builders. Their different approaches to training and overall calorie intake, not the protein, leads to obviously different results on their physique and condition.
What the science says about the right amount of protein
There are outliers in both directions, but the scientific and practitioner consensus is settling on the range of 1.4-2.2 grams of protein daily per kilogram of body weight for people doing regular endurance training.
Interestingly, that requirement seems largely unchanged by gender or for older athletes.
But there is a catch. The digestive system can only handle so much at once before it starts just throwing away excess protein. You can’t just sit down before bed and eat 11 eggs to catch-up. Sorry.
A safe assumption is to limit protein serving per sitting to 25-35g, or a quarter of your daily total.
A quick way to calculate protein requirements for meals and snacks
Take your weight in kilograms
Multiply by 4
Divide by 10
This is the amount you should aim to consume in each of your three main meals.
Now take the same amount and divide in half.
That’s the amount you should consume in each of two snacks.
Working off a conservative, lower-end estimate of 1.6 g / kg / day.
References / further reading:
Dietary protein for athletes: from requirements to optimum adaptation, Journal of Sports Science, 2011
How much protein can the body use in a single meal for muscle-building? Implications for daily protein distribution, Journal of the International Society of Sports Nutrition, 2018
Protein metabolism in women and men: similarities and disparities, Current Opinion in Clinical Nutrition and Metabolic Care, 2011
Evenly Distributed Protein Intake over 3 Meals Augments Resistance Exercise–Induced Muscle Hypertrophy in Healthy Young Men, Journal of Nutrition, 2020
Protein Requirements for Master Athletes: Just Older Versions of Their Younger Selves, Sports Medicine, 2021