Research

Macro partitioning

Endurance athletes require a daily protein intake of approximately 1.8 g/kg body mass per day, which may increase to >2.0 g/kg/day during carbohydrate-restricted training or on rest days.

Aim for 1.8 grams of protein per kilogram of body weight every day. If you are doing low-carb training sessions or taking rest days, bump this up to over 2.0 grams per kilogram. This helps your body repair muscle and replace amino acids lost during exercise.

GoodSupportsHIGH confidence
Based on findings from a series of contemporary protein requirement studies, the evidence suggests a daily protein intake of ~ 1.8 g·kgBM−1·day−1 should be advocated for endurance athletes, with the caveat that the protein requirement may be further elevated in excess of 2.0 g·kgBM−1·day−1 during periods of carbohydrate-restricted training and on rest days.
Oliver C. Witard et al. · Sports Medicine · 2025

Why this rating

Based on multiple controlled metabolic studies using the Indicator Amino Acid Oxidation (IAAO) method.

Source

Protein Nutrition for Endurance Athletes: A Metabolic Focus on Promoting Recovery and Training Adaptation

Oliver C. Witard et al. · Sports Medicine · 2025

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