Sometimes slower is better - especially when it comes to the rate of protein digestion. While rapid protein absorption is desirable immediately before or after exercise, delayed release is probably more beneficial throughout the remainder of the day.
Casein proteins are pH sensitive and gel in the acidic environment of the stomach. As a result, it can take more than twice as long for caseins to be broken-down into their amino acid subcomponents than whey and other proteins. Because of these unique "time-released" qualities, caseins are aptly described as being anti-catabolic, or muscle-protecting, proteins.
Another benefit is increased satiety (feeling of fullness or satisfaction). Casein exerts a slight pressure on the stomach walls. In effect, this pressure signals to the brain to stop eating because the stomach is full. Casein is the most slowly digested and absorbed type of protein. This helps create a "timed-release" effect, providing a steady stream of amino acids to your muscles over a long period of time. The net result is a greatly enhanced anti-catabolic environment which is much more friendly to growth and recovery.
Bodybuilders and athletes looking to build lean muscle, prevent muscle breakdown, and reduce recovery times, and individuals interested in improving the quality of their sleep can greatly benefit from casein.