Pneumatic resistance machines, such as the Keiser, use a compressor that creates pressure (resistance) to lift against, as opposed to actual weight.
One advantage to these machines is that because you are not actually lifting dead weight, you cannot build up momentum and “cheat.”
Now a study shows another unique benefit — they can help boost muscle power.
Researchers from the University of Waterloo (Ontario) found that when subjects did the bench press using a pneumatic machine, they were able to perform reps with significantly more speed and power than when they did the free-weight bench press.
If your gym has a pneumatic machine, use it at the start of your workouts to build more power.