We all know it, being active is part of the equation for living a healthy life. Add in lean proteins, veggies and super foods, subtract refined sugars, and divide your workouts between weight lifting and cardio. But what exercises really sum up to the greatest results and which should you abandon altogether? Equinox fitness manager Stephen Salzmann clears up the confusion on which exercises are most effective so you can trim down and get fit fast.

Why? “A sit up does very minimal abdominal activation and can put unnecessary pressure on your spinal disks. It can also contribute to bad posture,” says Salzmann.

Swap with: Planks
“Planks are the most effective exercise for strengthening your abdominal muscles by training your core to resist flexion and extension. Your core is meant to stabilize your body, so do exercises that build stability.“

Behind the neck barbell press and pull
Why? “Doing this movement behind the neck is extremely tough on your rotator cuff. It puts your shoulder in a provocative position, which can lead to injury.”

Swap with: Front press and pull
“Adjust this movement by standing in an upright posture, press and pull the barbell in front of your face. By making this small change, you’ll isolate those back muscles without the risk of injuring your shoulder.”

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Knee extensions
Why? “Knee extensions on the machine are meant to build your quad but this exercise puts an incredible amount of force on your knee joint, especially in the first 30 degrees of movement.”

Swap with: Squats
“Instead of going to the knee extension machine, do your squats. Done properly, these are much more effective at toning your legs.”

Smith Machine squats
Why? “Doing squats on an assisted machine like the Smith Machine can worsen your stability (read: core) and mobility.”

Swap with: Free weight squats
“Free weights are a great way to intensify your squats. The free weights force you to activate more muscle groups like your glutes, quads and core, while improving your movement and stability.”

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