casein

casein considered the opposite of whey protein. It is an insoluble, slow-digesting protein. In sports nutrition, casein is used as a long-digestible supplement. Casein has an anti-catabolic effect, but does not increase protein synthesis.

Casein takes at least 2,5 hours to digest, and in some cases, 4 hours. This is why casein is considered a good sports supplement to consume some time after training (or on non-training days). Casein is very good to consume before bed, as for 3-4 hours the body will receive a slow flow of amino acids, which prevents muscle breakdown.