When it comes to protein shakes, I use a Whey protein. I prefer Whey protein compared to Casein protein due to its absorption rate (meaning it gets to where it's needed in a rapid fashion). Also, because of how it provides the body with the perfect amino acid profile, and how you get the most bang for your buck since Whey is about 90 percent pure protein. I’m not a big fan of Casein, but it does have its beneficial value. Casein is a time released protein which is advantageous to use if you’re not going to have another meal for an extended period of time, or before bed due to your 6-9 hour fast. I just feel that when I use Casein, i hold some water and show a softer look then i would with Whey, but that's just me. This leads me into when to have your protein shakes? Well most importantly you need a PWO (Post Work Out) shake. The goal of a post workout shake is to replenish the fuels lost from your workout and to stop muscle breakdown. Most importantly to provide the fuel you need for muscle growth. This protein shake is taken after a workout (within 20-30 minutes after completion) in conjugation with carbohydrates. Your muscles are yearning for fuel and are severely glycogen depleted, so this is the best time for absorption to occur. (You have an anabolic window within the hour for maximum absorption). You need to add carbohydrates for the simple reason that protein taken in cannot be stored in the body, so the carbohydrates are used (spike in insulin) to help shuttle the protein into the muscles where they will be used. If carbohydrates are not consumed in a timely manner post exercise, your glycogen replenishment is hindered. This is the same for protein for if you do not consume protein, your performance, protein synthesis, and ultimately muscular hypertrophy, will be hindered as well. Vincent Russo, 25 years old from Kenilworth NJ. Has a BA in Biology from Fairleigh Dickinson University in Madison NJ. A Bodybuilding.com Team Athlete, Silver Model, High School Football Coach, Substitute Teacher, Waiter/bartender. Was a top 5 finalist out of 500 guys for bodybuilding.com‘s 2012 BodySpace Spokes Model. Compete in the Men’s Physique category where in recent competitions placed 2nd in NPC East Coasts (Nov. 2011), and 3rd in Bodybuilding.com‘s BodySpace Spokes model competition (LA Fit Expo 2012).