“Because weights machines require less skill and motor control than free-weight exercises, they’re typically safer than free weights and cause fewer accidents and injuries,” says Servante.

Under the guidance of a PT they can also be used to get people working close to failure, which is a key component of building muscle, sooner than they would if they had to master the form of a free-weight exercise. “They are a highly effective tool to increase the client’s strength in key movement patterns in a short period,” says Servante. “This allows me to get my clients to a point where they can train close to failure and accumulate higher amounts of training volume, two key drivers of hypertrophy.

“It is often safer to train closer to failure on machine exercises, as it is far less likely for your technique to break down and cause you to fail. This is beneficial because your muscles are more likely to fail than your technique. This element is true for both beginner and advanced trainees.

“Some machine exercises also have better resistance profiles than free-weight exercises. A resistance profile essentially reflects which portion of a lift is most challenging and which is easiest, or in which portion you need to exert the most and least force. 

“For example, during a dumbbell Romanian deadlift, the exercise is ‘harder’ at the bottom and ‘easier’ as you reach the top. This is important because some machines have resistance profiles that match where you’re physically stronger or weaker in a lift, which research shows can be beneficial for muscle growth and help develop all portions of a given muscle. 

“Put simplistically, your muscles can produce less force when they’re ‘short’, such as at the top of a hip thrust when you clench your glutes, and your muscles can produce most force through their mid-range, such as when your forearms are parallel to the floor in a standing biceps curl. 

“Some exercise machines reflect this with a bell-shaped resistance profile, where the resistance increases through the middle of the lift before starting to lower as you reach the top. These machines have been designed to target certain muscle groups in a way free weights cannot. You would struggle to replicate the resistance profile of a lying hamstring curl with dumbbells alone, for example.”