Because solid food takes more time to digest and to break down the protein and send it to the muscles, it can be best to take a protein shake immediately following a workout, since protein shakes only take about 30 minutes to reach the muscle after ingestion.
selectivity. (analytical chemistry). The ability of a type of method or instrumentation to respond to a specified substance or constituent and not to others. (electronics). The ability of a radio receiver to separate a desired signal frequency from other signal frequencies, some of which may differ only slightly from the desired value.
Analytical figures of merit such as selectivity are performance characteristics of an analytical determination. They can be used to select between potentially useful methods and to evaluate or optimize a method that is already in use. The importance of analytical figures of merit is generally accepted.