Question: "What is the Smith machine, and should I be using it?"
Answer: Though it might look intimidating, the Smith machine is actually more like a barbell with training wheels, says John Jay Wooldridge, a personal trainer in New York City. A rack and cable system and locking mechanisms ensure that the weights won't fall — even if you let go. This allows you to increase the challenge of lunges, squats, and bench presses without fear. Use the Smith machine if you're already proficient in these moves, but ask a trainer to give you a quick tutorial first, Wooldridge says.