"Weighing The Benefits: Whey & Casein Protein" was written by Dr. Kevin Sprouse. Dr. Sprouse is a team physician for the Cannondale Drapac Pro Cycling Team. He has a degree in exercise science and has board certifications in both Sports Medicine and Emergency Medicine. He practices at Podium Sports Medicine in Knoxville, TN. You train hard, presumably with the intent of getting stronger, fitter, and faster. This beneficial adaptation occurs after your workout, not during. The process begins as soon as your effort stops. The immediate or acute component consists of refueling and stopping the muscle breakdown. This step is crucial, especially when doing consecutive days of training, and nutrition is a key component of this process. You’ve likely heard that you should consume some amount of carbohydrate and protein within a defined window of time after exercise. There is some gray area here, and the specifics are dependent on the athlete’s goals, but there is no denying the fact that adequate protein is a nutritional requirement post-workout. There are many ways to fulfill this protein requirement. I’m a fan of eating real, whole foods when possible. In pro cycling, we always have a big pot of rice and protein (eggs, chicken, etc.) for the rides to eat after the stage. But before they dig into this, they all go for a recovery drink first. Why? It’s often the case that a hard workout leaves you without much of an appetite initially. Most athletes don’t want to eat something dense and filling as soon as they finish their prescribed workout or race. To ensure that they start to meet their need for protein, many turn to a protein drink, most of which contain whey protein. Whey protein has been used for years because it is readily available and easy to produce. Whey is one of the proteins found in milk, the other being casein. Often, whey is collected as a byproduct of cheese production. As with any supplement, there are good sources of whey and there are those companies which are simply looking to make a buck off the waste material generated from making cheese. Many whey products are of poor quality and can cause significant gastrointestinal distress. However, a high-quality whey protein is quickly absorbed and can be a fantastic addition to an athlete’s dietary regimen. The other milk protein that is sometimes used as a dietary supplement is casein. Casein is a complete protein that is absorbed much more slowly than whey. Where whey can be a great supplementary protein to use after exercise, casein is often used by athletes before bed. The goal of protein intake is to promote an anabolic state (muscle building) as opposed to a catabolic one (muscle breakdown). If you’ve had a particularly hard day of training, are doing consecutive days, or are aiming to build muscle, consuming casein at bedtime can help your body remain anabolic overnight. Both whey and casein can be used to meet your overall protein intake goal. For most athletes, this is going to fall somewhere between 1 and 2 grams of protein per kilogram of body weight per day. Where you fall on this spectrum will be determined by your goals. If you want to maintain weight, you might be aiming for 1-1.5 g/kg. If you want to gain muscle, something closer to 2 g/kg will make sense. I generally recommend 1.5-1.8 g/kg per day for most endurance athletes. Personally, I’ve never actually been a big fan of whey protein. Don’t get me wrong, it has been shown again and again to be a useful supplement when used correctly. But I’ve worked with many athletes who just don’t tolerate it well. (I have experienced the same issues with whey.) Not only can it cause digestive upset, but many products taste synthetic and bitter. I like to enjoy the food I eat! Recently, though, I tried a new product called Ascent. This is, hands-down, the best tasting protein supplement I’ve tasted. (Full disclosure: They did send me some free product to try, but I’m not getting paid to say I like it!) I also had no problems digesting it. As I mentioned, like any food or supplement you consider consuming, the quality of the product makes all the difference. Whether your goal is to lose weight, gain muscle, increase strength, or improve your speed, ensuring adequate protein intake is crucial. Real food sources are best, but it can be difficult to meet your needs with food alone. A high-quality protein supplement should be one of those nutritional products that every athlete keeps in their pantry.