As your body can quickly digest and use the protein in whey, it is great for replenishing your protein stores immediately after a workout. While your body doesn't process creatine as quickly, this chemical helps to increase energy availability. By increasing the amount of energy available for working out and muscle building, regularly taking creatine can boost your training gains. Unless you have reactions to either of these on its own, a combination of creatine and whey makes a safe and effective post-workout supplement.
Whey protein supplements come in different forms, including whey protein concentrate and whey protein isolate. These products differ in their lactose content, concentration and fat content, with whey protein isolate containing less fat and lactose than other forms. Despite these differences, all forms of whey protein contain a complete amino acid profile. As your body quickly processes whey protein, it is ideal for the post-workout recovery period. To help avoid stomach issues due to high milk fat intake or lactose sensitivity, however, you should choose whey protein isolate over other forms.
Without any supplementation, your body produces adequate amounts of creatine. Adding a supplement increases circulating levels of creatine, thus increasing your the availability of energy stores for your workout and recovery. As your body takes hours to process creatine supplements, it is most effective when taken regularly over a long period of time. While an intense workout depletes your body's creatine levels, taking a supplement after your workout has little immediate impact. Although it helps to simplify your supplementation regimen, there is no physiological benefit to taking creatine after your workout as long as you take it regularly.
While a few grams of creatine per day is an effective dose, whey protein supplements are most effective in large amounts. Because of this, creatine has almost no effect on the texture, flavor and weight of your post-workout supplement. As your body processes these supplements at different speeds and there are no interactions between the two, taking whey and creatine together has little impact on their effectiveness. Due to this lack of interaction, a combination of whey and creatine does not cause any negative reactions that aren't present with either supplement on its own.
While the time at which you take creatine is not important, regularly using both whey and creatine makes your workouts more effective. Compared with using no supplements or taking either on its own, nutrition and sports medicine expert Dr. Mauro Di Pasquale states that regularly taking creatine and whey leads to greater gains in lean muscle mass and strength. Aside from helping to ensure that you take it regularly, however, there are no benefits specific to adding creatine to your post-workout whey protein supplement.