I recently read a good article with some pretty common misconceptions about muscle building. Here are 7 myths that maybe you've heard... debunked.
#1: Lifting really slowly builds really big muscles.
Lifting slowly does not help you build muscle, it just makes your workout go really slow. Actually it means you burn fewer calories, too. As I've mentioned before, doing circuits and supersets gets your heart rate up and helps you burn fat as you build muscle. Experts say to do the up phase of an exercise as fast as possible, the down phase a little slower and more controlled.
#2: Swiss balls are more effective than benches.
The ball is great for abs, and it forces you to use your abs more if you're doing a chest or shoulder lift on one. But it also means that you have to do less weight. To build more muscle, a traditional bench for those exercises is more effective.
#3: Free weights are better than machines.
If you're inexperienced, machines are often better than free weights. For example, if you can't complete a pull-up, then lat pulls are your next best option, using a machine. Machines can also be more effective at isolating certain muscles. So don't discount machines completely... they can be good for some things. However, if you are more experienced, you should stick to free weights for the most part.
#4: The more protein you eat, the more muscle you build.
There is no question that protein is very important to building muscle, and you definitely should make sure you're getting enough. But, you can also get too much. The experts say that if you're working out hard, you need .9 to 1.25 grams of protein per pound of body weight. If you get too much, excess just becomes waste or is converted to carbohydrates and stored. So get enough protein, but there's no need to go overboard, because it'll do more harm than good.
#5: Leg extensions are safer than squats.
Not if you know how to do squats right. And it's also interesting that a recent study found that single joint activation exercises, i.e. the leg extension, can be more dangerous than those that use multiple joints. Squats are a lot more effective too.
#6: Never exercise a sore muscle.
First determine how sore you are. If the muscle is sore to the touch, or limits your range of motion, give it another day. If that's not the case, then a workout might actually do your muscles good by helping to stimulate blood flow, which eliminates waste and speeds the repair process. But if you're sore and you're still going to workout, you're better off going easier than you normally would. Also, that doesn't mean that you should work the same muscle groups day after day. They need a day or two of rest, so don't get overzealous.
#7: Stretching prevents injury.
Studies show that injuries happen in your normal range of motion for the most part. Stretching does help you to become more flexible of course, and that has its benefits. But what helps prevent injury in a workout is the warmup, which does exactly what it sounds like. It increases bloodflow to your muscles, which help them get ready for the stress that's coming. By the way, stretching when your muscles are warmed up gives better results in increasing flexibility than stretching "cold".