Protein for muscle growth: what the evidence supports

The useful question is not “which protein powder builds the most muscle?” It is whether a person who resistance-trains is eating enough high-quality protein across the day. Supplements can close a gap. They do not create the training stimulus.

Do not turn 1.62 into a magic number

The 1.62 g/kg estimate is a group-level breakpoint with uncertainty, not an individual ceiling. Training status, energy intake, age, food quality and adherence change the practical target. During a calorie deficit, lean resistance-trained athletes may benefit from the upper end or above, but the evidence is less clean than supplement marketing suggests.

Timing is secondary to the total

Protein near training is convenient and biologically sensible, but the day’s total intake and a repeatable meal pattern matter more than racing a supposed 30-minute anabolic window. The ISSN position stand suggests spreading protein feedings across the day, commonly every three to four hours.

Where powders fit

Whey, casein and plant blends can all be practical. The audit questions are simpler than the label: how much complete protein does a serving deliver, is the amount independently verified, what else is added, and what is the cost per useful serving? A powder that helps a user hit an appropriate intake efficiently can be valuable; a “muscle matrix” hiding doses behind a blend cannot.

Limits and safety

The ranges above describe generally healthy exercising adults, not people with kidney disease, pregnancy, eating disorders, paediatric needs or other medical constraints. Those cases require individual clinical advice.