If there's one thing that separates the gym newbies from the pros, it's their choice of training equipment. Most experts spend their time hitting the free weights hard, while noobs spend their time using machines. However, there are a few machines that even the experts should try if they want to maximize their workout.

Rowing Machine

Rowing is tied with swimming for "the best cardio workout," but it's also great for developing strength in the posterior chain muscles (back, lower back, glutes, hamstrings, and calves), shoulders, and arms.

Lat Pull-Down Machine

Pull-Downs are among the most effective exercises to engage the latissimus dorsi muscles in your upper back. The Pull-Down machine gives you a wide variety of exercises to try (wide grip, narrow grip, regular grip, underhanded, one-handed, etc.) in place of Pull-Ups or Chin-Ups.

Horizontal Seated Leg Press

Instead of hitting the Squats hard, switch things up and give this machine a try. Used properly, this machine can effectively work every muscle in your legs. It'll change the direction of the movement (horizontal instead of a vertical plane of motion) and reduce lower back strain.

Cable Machine

If you're lucky enough to have an all-in-one cable machine, take advantage of it! Cable Curls are more effective than regular Curls because of the continuous tension on your muscles. The same goes for Cable Pushdowns — they're more effective than Skull Crushers or Kickbacks. Cable Machines offer a wide variety of exercise options that will keep your muscles engaged through the full range of motion.

Hanging Leg Raise Machine

This isn't as much a workout machine as a stand where you grip handles and support your weight on the padded elbow cushions. Hanging Leg Raises are amazing for your core and hip muscles. You can do Straight Extensions, Knee Raises, and a whole range of exercises to shred your abs, sides, and hips.

Leg Extension Machine

Let's be clear: leg extensions are not the most efficient workout option. They place all the strain on your knee joint without engaging the thigh muscles (quads) efficiently. However, it's the perfect "finisher" for your intense leg workout. Once you've done all the Squats, Lunges, and Leg Presses you can handle, finish with a couple sets of Leg Extensions. The continuous tension on your leg muscles will make for a killer end to the workout, even if you use less weight.

Leg Curl Machine

Leg Curls are the less-effective cousin to Deadlifts, but they can be a good option if your back is giving you trouble. Deadlifts and Stiff-Legged Deadlifts engage your lower back muscles effectively as they hit your glutes and hamstrings. However, they can also strain your lower back (even if you have proper posture). The Leg Curl machine gives you a way to train your hamstrings while giving your spine a break.

These are the only machines you should use at the gym. Everything else —from the Chest Press Machine to the Fly Machine to the Squat Machine — should be avoided. Free weights are the smarter option and will lead to better muscular development overall.

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