When entering a gym for the first time, the decision to use machines or free weights can be tough. But when it comes to muscle growth, which one is better? According to Dr. Mike Israetel, the question itself is framed wrong. Instead, the focus should be on which exercise effectively targets the desired muscle. By following the 7 training principles, you can select the best exercises for your goals. Free weights offer benefits such as increased muscle activation and functional movements, while machines provide stability and safety. Combining both can lead to optimal muscle growth.