machines and free weights can be used for muscle hypertrophy as long as your adding more load each session. Alot of bodybuilders use both in their training to hit every muscle.
basic knowledge -
muscles grow in response to the degree of loading placed upon them. So, in reality it doesn’t really matter how the loading is placed on the muscle just as long as it is sufficient to stimulate the muscle to be active. If muscle hypertrophy is your only concern it probably doesn’t make a big difference if you use machines or free weights to achieve this goal
However since the OP posted this in the strength/PL section
taken out of the NCSA manual
There has been studies done to show that free weights in strength/athletes are more beneficial.
- Most people don’t realize that your strength level is not just determined by how big you muscles are, but also by your nervous system. Your nerves adapt to resistance training just like your muscles do. Their structure and function change to allow you to lift more weight.
There are some studies that indicate that strength gain due to free weight training is more beneficial to the performance of daily tasks or athletic activities as well.
- Free weights involve free-form which requires you to use more muscles for a given exercise. For example squatting with a barbell requires you to balance the weight on your back, to balance yourself (so you don’t fall over) and thus requires a lot more muscle activation than a machine exercises. Improvement in bone mineral density has also been
shown to be greater with free weight training6. These studies indicate that there might be some additional benefits in using free weight exercises over machines.