While free weights allow freedom of movement, a weight training machine automatically places you in the correct biomechanical position to accomplish the exercise motion in the proper form. The machine effectively isolates the muscles that you are using, and all you have to do is push or pull the weight. Your movement is restricted because you can only move the weight in one direction.
2. Safe to use
Weight training machines are typically safer to exercise with compared to free weights. The limited range of motion prevents you from using your muscles incorrectly. Weight training machines also eliminate accidents such as dropping a barbell that you are trying to lift.
A weight training machine is ideal for those who have an injury and are undergoing physical rehabilitation through strength training. An exercise machine is also useful if you are working with heavy weights and do not have a spotter.
3. Faster workouts
In general, it takes less time to complete your exercise when working out with a weight training machine rather than free weights. When working with free weights, you have to remove or add plates on a barbell. On a weight training machine, you can quickly adjust the weight by moving a pin or clipping cables to the desired resistance setting. This allows you to go through your exercise routine faster while maintaining an elevated heart rate.