You already know that there are different body types. All of us at some time or another have probably looked a bit jealously at some guy at the gym who doesn't seem to hardly have to break a sweat to put on muscle mass. On the flip side, we've all seen the really skinny guy who no matter what he seems to do, can't seem to bulk up. And lastly, there's the stocky guy who really struggles to get into shape, but when he goes on vacation, taking a break from his routine he comes back looking like he hasn't been to the gym in years. This poor guy can't seem to walk past a donut without putting on fat.

These are exaggerations but they're not that far from the truth. Some guys find it easier than others to put on muscle and stay lean-other guys can't put on muscle no matter what they do, while still others can't seem to lower their body fat regardless of how much cardio they do. In all of these situations, genetics-specifically body type-is somewhat the culprit.

There are three basic kinds of body types: Ectomorph, Mesomorph and Endomorph. Each of these has its own unique set of general visible characteristics-the obvious things you see on the outside. And in addition, each has its set of internal characteristics-the stuff that's not so obvious like metabolism. Knowing about these different body types, their unique qualities and how they operate and respond to weight training and diet can help you achieve your goals no matter what kind of body type you happen to be.

The ectomorph is the naturally skinny guy. He is the hardgainer-meaning that for him, putting on mass is really tough. He can lift hard for weeks on end and realize only minimal gains. Typically, an ectomorph is very lean and has a small frame, more or less a flat chest, skinny shoulders and a fast metabolism. These are the guys who seem to be able to eat just about anything they like without putting on weight.

An ectomorph who just walks into the gym and jumps into a random bodybuilding regimen he found in a magazine is more than likely going to be really disappointed with the results. In order for him to get the results he wants, he's got to take the time to understand the nuances of his body type and what it requires in order for him to put on mass. For him, he's got to focus not just on lifting weights but also on making sure he's taking in enough calories to be able to build muscle. He should also give his muscles plenty of time to recover between training sessions-more time than other body types-and avoid most cardio.

The endomorph is the naturally athletic body type. They tend to be stronger, larger-framed and rectangular-shaped with well-defined muscles. These are the guys who sometimes make putting on mass look almost effortless.

That's really not the case though-it just seems like some of them don't have to exert themselves very hard. The reality though is that for most endomorphs, gaining muscle mass is a lot easier than for an ectomorph. On the downside-it is also a lot easier for an endomorph to put on fat than it is for an ectomorph, so they've got to be careful or they can quickly lose their gains and go from "athletic" to "dumpy" in no time. For most endomorphs, an ongoing regimen of weight training and moderate cardio is the best mix.

The mesomorph is the third body type. These guys tend to be shorter (but not always) and generally have thick arms and legs. They are the guys who are naturally strong-especially in the legs. Mesomorphs are usually able to put on muscle relatively easily. Powerlifters, strongmen and competitive bodybuilders are often mesomorphs. Unlike ectomorphs though, the mesomorph metabolism runs a lot slower-meaning that it's also a lot easier for them to put on fat. A mesomorph who wants to remain lean will have to be sure to mix in plenty of cardio with his lifting.

Regardless of your body type it's important to remember not to "blame" anything on your genetics-you're not condemned to looking a certain way simply because you happen to have a particular body type. Armed with the knowledge of your body type and understanding its unique characteristics you can achieve your body building goals, whatever they may be.