Macro partitioning
Current Canadian Recommended Nutrient Intake (RNI) for protein (0.86 g/kg/day) is inadequate to maintain nitrogen balance in habitually exercising male and female endurance athletes, resulting in negative nitrogen balance.
If you are an endurance athlete, the standard recommendation of 0.86 grams of protein per kilogram of body weight is likely not enough to keep your body in a neutral protein state. You are likely losing muscle protein even if you eat enough calories. Consider increasing your protein intake above this baseline to support recovery and maintenance.
Our data showed that dietary intakes of ~0.86 g protein . kg-1 . day-1 [the current Canadian RNI (10)] were inadequate to maintain nitrogen balance in habitually exercising males and females (Fig. 2).
Why this rating
Small sample size (n=6 per group) but rigorous methodology (isotopic tracers, controlled diet, nitrogen balance).
Source
Gender differences in leucine kinetics and nitrogen balance in endurance athletes
Stuart M. Phillips et al. · Journal of Applied Physiology · 1993
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