Definition
Whey protein is derived from milk and is one of the most bioavailable complete proteins available. Whey isolate has 90%+ protein with minimal lactose; concentrate is 70–80% protein and cheaper; hydrolysate is pre digested for fastest absorption. It's a convenient way to hit protein targets, not a magic muscle builder.
Real questions
Whey isolate or concentrate?
Concentrate is fine for most people. Choose isolate only if you're lactose intolerant or counting every carb in prep.
When should I take whey protein?
Whenever you need protein. The 'anabolic window' is largely myth — total daily protein matters far more than timing.
Stack with
Put it to work
Coach Foster builds your program around whey protein and the rest of the fundamentals, shaped to your body and your week.