The anabolic window is the idea that you have 30 to 60 minutes after a workout to eat protein or your gains slip away. The concept is mostly a myth. Training does make muscle more sensitive to protein, but that heightened state lasts many hours, not minutes. Total daily protein and how you spread it across meals matter far more than sprinting for a shaker.
Why it matters
The window idea caused a lot of unnecessary stress. Lifters chugging shakes in the parking lot, panicking over a delayed lunch, treating a normal meal two hours later as a wasted session. None of that holds up. When researchers pooled the timing studies, the apparent benefit of immediate post-workout protein basically vanished once total daily intake was matched. The lifters who grew were the ones eating enough protein, period. Timing was noise.
One honest caveat. If you trained fasted, your last protein feeding was a long time ago, so eating reasonably soon after does make sense.
How to use it in training
Get your daily protein target right first, somewhere around 0.7 to 1 gram per pound of body weight for most lifters. Then split it across three or four meals with 25 to 40 grams each.
Do that, and post-workout timing takes care of itself. A normal meal within a couple hours of training is plenty. Eat before you train? You're covered even longer, since that protein is still digesting while you lift.
Related terms
Go deeper
We walk through the actual timing studies here: The anabolic window myth.