The American and Canadian guidelines recommend a daily protein dietary allowance, measured as intake per kilogram body weight, is 0.8 g/kg. This requirement is for a normal sedentary person.
Several studies have concluded that active people and athletes may require elevated protein intake (compared to 0.8 g/kg) due to increase in muscle mass and sweat losses, as well as need for body repair and energy source. Suggested amounts vary between 1.6 g/kg and 1.8 g/kg, while a proposed maximum daily protein intake would be approximately 25% of energy requirements i.e. approximately 2 to 2.5 g/kg.