What a 2025 review says about protein for runners, cyclists and other endurance athletes, and how to turn it into meals.
Endurance athletes probably need more protein than they eat. A 2025 review in Sports Medicine by Witard, Hearris and Morgan found that a typical endurance athlete takes in about 1.5 g of protein per kg of body weight a day.
What the research recommends
The same review says about 1.8 g/kg a day should be advocated. It’s a narrative review, which means an expert summary of the studies rather than a new trial.
Key things to know
- The daily target is about 1.8 g/kg, up from the 1.5 g/kg athletes typically eat (Witard et al., 2025).
- Needs may go past 2.0 g/kg on rest days and during low-carb training (Witard et al., 2025).
- Per-meal advice is preliminary: about 0.5 g/kg right after exercise, but the authors say there aren’t enough studies for firm per-meal rules.
- Protein during a session doesn’t help performance. The review found no compelling evidence that it does when your carbs are covered.
Digging into the numbers
Low-carb training and rest days
Some athletes train with low carbohydrate or low energy availability on purpose. The review says protein may help the body adapt in those conditions, and that needs can climb above 2.0 g/kg (Witard et al., 2025). Talk to a clinician or sports dietitian before cutting carbs or calories hard.
What about timing?
The old idea of a short post-workout window doesn’t hold up well. A meta-analysis of 23 resistance-training studies found total protein intake was the strongest predictor of muscle gains, and its authors said the results refute the belief that timing around a session is critical. That was strength training, not endurance, so treat it as a hint. For endurance, the review suggests about 0.5 g/kg after exercise as a reasonable target while saying the evidence is preliminary.
Key takeaway: Hit your daily total first. Spreading it across the day is a sensible habit, not a magic window.
Putting it into practice
Take a 143 lb (65 kg) athlete. At 1.8 g/kg that’s about 117 g a day, and 0.5 g/kg is about 32 g after a hard session. A day might look like this:
- Breakfast: eggs, Greek yogurt, oats and berries
- Lunch: chicken, quinoa and greens
- Snack: whey, banana and milk smoothie
- Dinner: lentils, sweet potato and tahini
You don’t need to hit the same number at every meal. Proteinly is built around a protein-first approach without calorie counting, and its automatic eating timer reminds you to eat every 2 hours, which makes spreading protein through the day a habit instead of a chore. It helps you reach a target; it doesn’t make the target more effective. For more on spreading protein, see protein needs after 40.
Frequently asked questions
Should I take protein during a long ride or run?
The review found no compelling evidence it improves performance or glycogen restoration when carbs are adequate (Witard et al., 2025).
Does this apply to women?
Probably, but studies built for female endurance athletes are still a gap, so use the number as a starting point.
Next steps
Work out 1.8 × your weight in kg, spread it over your meals, and bump it up on rest days. Build the habit at Proteinly, follow YouTube @Proteinly, and remember: Build the Habit. Build the Body.