For young men who exercise regularly, eating more than 2.0 grams of protein per kilogram of body weight per day does not lead to significantly more muscle gain than eating less than that amount over an 8-week resistance training program.

If young guys lift weights hard and do intense workouts while eating less for a month, chugging 2.4 grams of protein per pound of muscle each day helps them gain more muscle and lose more fat than eating half that much protein.

Young men who lift weights for muscle growth and eat more than 2.0 grams of protein per kilogram of body weight each day tend to get stronger on average than those who eat less than that amount, based on improvements in their squat, bench press, and deadlift numbers over 8 weeks.

If you're lifting weights and want to build muscle, eating at least 1.6 grams of protein per kilogram of body weight every day is the biggest factor that helps — more protein means better results, and when you eat it doesn't matter as much.

In young men who lift weights recreationally, eating more than 2.0 grams of protein per kilogram of body weight per day led to slightly greater increases in strength over 8 weeks compared to eating less, even though muscle size increased similarly in both groups. This suggests that strength gains may come from improvements in how the nervous system controls muscles or in lifting technique, rather than just from muscle growth.

When athletes are trying to lose weight by eating fewer calories, eating more protein (about 2.3 grams per kilogram of body weight) helps them keep more of their muscle compared to eating less protein (about 1 gram per kilogram).