That's Fit

Generally speaking, there are three basic speeds at which protein can be released: Slow, Medium, and Fast. Pretty straightforward, right? However, what might not be so obvious are the known effects each type of release will have on your body.

Here's a quick look at different types of protein sources and how their release speeds play a role in their functionality.

Slow Release

Sources: Whole food protein sources (chicken, beef, fish, etc.), casein protein

Effects: Causes a gradual increase and maintenance of blood-amino-acid levels for a long duration of time. Will also keep you feeling full for an extended period of time.

Medium Release

Sources: Milk-protein isolate, soy-protein isolate

Effects: Provides a bit less of a gradual increase of blood-amino-acid levels but helps them from eventually dropping rapidly. Will keep you feeling full for some time, but not quite as long as most slow-release protein sources.

Whey protein is incontrovertibly one of the most widely used and accepted forms of protein available in supplement form. While some people avoid whey because it is a derivative of milk and/or milk products, others make a whey protein shake or two part of their daily diet. But, enter into any GNC or Vitamin Shoppe store and you'll immediately feel a wave of whey protein confusion roll right over you. There are so many brands and types of protein to choose from!! Well, to help you along, I'll at least explain the difference between whey protein concentrate and whey protein isolate.

As I said, I'm not going to get into a battle of the brands. That discussion is better left for weightlifting and nutritional supplement forums you can find with a quick Google search. However, I will do my best to help you decide if concentrate or isolate is better for you y explaining what separates one from the other. Starting first with whey protein concentrate, this form of whey protein is not as potent as isolate. It can contain anywhere between 29 and 89 percent protein. And, as the amount of protein in concentrate decreases, the amount of fat and/or lactose usually increases. As for whey protein isolate, this purer version contains at least 90 percent protein and little to no fat and lactose.

As you'd probably expect, whey protein isolate is more expensive than concentrate. But as the numbers show, you may actually be getting more for your money. In either case, don't just rush out and buy a giant jug of protein powder. Always speak with your doctor before taking nutritional supplements of any kind, whey protein certainly notwithstanding.

For more information on whey protein, visit the Whey Protein Institute's website by clicking here.

Probably not, but depending on what your goals are you might. And although they're intimidating for most people (no, taking them won't balloon you up like the Arnold Schwarzenegger of old) they really aren't that complicated. Buying muscle-building supplements is just like anything else health related: it's all about assessing your lifestyle and reading labels.

The most common supplements used for building muscle mass include creatinine, sports drinks, and whey protein. Creatinine is found in the body naturally and is used to fuel short bursts of intense activity, sports drinks provide a good balance of energy and protein, and whey protein is great for post-workout muscle repair. Read this article for more tips on how and where to start if you're considering supplements for your workout, and there's also a list of the best supplements to consider.