Macro partitioning

Resistance-trained men habitually consuming high protein intakes (>2.2 g/kg/day) experience attenuated post-exercise whole-body net protein balance when their intake is acutely reduced to moderate levels (1.2 g/kg/day), and this metabolic state requires 3-5 days to fully adapt.

If you are a regular weightlifter who eats a lot of protein (over 2.2g/kg), you cannot simply drop your intake to moderate levels (1.2g/kg) and expect your body to use that protein efficiently for muscle building right away. Your body has adapted to burning off excess protein, and it takes 3 to 5 days to slow down that burning process. During this week, your muscle building efficiency is lower. If you must reduce protein, give your body time to adjust, or maintain higher intake during the transition.