A lot of people debate about which one is effective when it comes to exercising and producing muscles. They often debate whether machines are more effective or free weights. Basically, barbells and free weights are classified as free weights. On the other hand exercises that have pulleys or cables to help you lift the weight are machines.
In order to gain muscles, you need to focus more on free weight exercises. For all machine enthusiasts out there, you might rethink about which one is more effective. Free weights are indeed more effective in promoting muscle growth. Although the exercises here are much more difficult to execute because nothing is actually assisting you to employ the correct execution, this fact alone is why free weight exercise is much more effective.
Free weight exercises are able to stimulate most of the muscle fibers as possible. This is impossible to do with a machine. Why?
Basically, machines lack in promoting stabilizers and synergist muscle development. Basically, these two muscles are what support the main muscles when you are performing a complex lift. For example, if you need to do bench presses, you need to be able to make use of the stabilizers and the synergist muscles in order for you to achieve lift. And, you need lots of it. If you bench press using a machine, it will not really need any assistance from the stabilizers as the machine itself is already supporting your main muscles.
Machines basically fail to stimulate the muscles around the area you are working on, which are the stabilizers. You need to remember that in order for your main muscles to grow, the stabilizers should be strong. And, the only way to do this is by doing as much free weight exercises as you can.