Canadian researchers had healthy men ingest whey protein, which is a fast-digesting protein, after resistance exercise. One group consumed one 25g serving of a protein drink at one feeding (called a single feeding). The second group sipped one 2.5g serving of a protein drink every 20 minutes over a 3-hour period (called a pulse feeding).
By the end of 3 hours, the subjects had consumed the exact same amount of whey protein providing identical amino acid profiles.
As expected, the single feeding group experienced a rapid increase in blood levels of amino acids, including leucine. The pulse feeding group experienced a more sustained and prolonged increase in amino acid levels over time.
The rate of muscle protein synthesis determined over a 3-hour period after exercise was significantly greater with the single feeding group (95%) compared to the pulse group (42%). Surprisingly, greater protein synthesis was also present 3-5 hours after exercise in the single feeding group (193%) than the pulse group (121%).
This research shows that consuming a fast-digesting protein like whey right after workouts provides both immediate and long-term benefits for protein synthesis versus sipping protein over a period of time.