"Proper" Number of Repetitions?

So, you're in the gym and you're trying to build muscle. Great! However, there is a common question that is often asked in and around the gym. How many repetitions should I do to build muscle?

To give a little bit of history behind this question, we will start back in 1954. Ian MacQueen, a surgeon and competitive bodybuilder came up with a theory. He believed that 8-12 repetitions was the secret number for building muscle. Now although this holds some truth, it is also very dependent upon another factor. The main factor responsible for muscle growth is called, time under tension. This is simply the amount of time in which you put your muscles under stress. Many people have a belief that you must lift the heaviest amount of weight to make you muscles grow. However, using heavy weights will cause a type of muscle growth which will lead to strength gains rather than size gains. Using less weight but more time under tension, will stimulate the muscles in a way which causes size increases. Both types of training have their benefits.

So what IS the best rep range for your workouts?

There is no set number. Vary your rep ranges and adjust the weights accordingly. This will ensure you stimulate every type of muscle growth, both in the slow and fast twitch muscle fibres. Your body is an extremely smart machine and will always adapt to what you are doing. If you constantly keep your body guessing, it will constantly have to adapt and change. This is how optimal growth and results occur.