WASHINGTON – As people kick start their New Year’s resolutions to lose weight, gym machines are getting extra attention. But not all equipment was created equally.

Some machines can cause undue stress on your joints and even lead to injury, says fitness expert Lisa Reed. She suggests substituting equipment for medicine balls or using your own weight for resistance:

• Seated leg extension machine: It puts too much pressure on your knees. Try a squat, instead, and get the added bonus of working your quads, hamstrings, abdominals and lower back.
• Chest press machine: Get the same results from regular pushups on the ground
• Seated shoulder press: Overhead pressing can hurt shoulder joints. Try standing dumbbell presses or bouncing a medicine ball off a high point on a wall.
• Seated rotation machine: Excessive twisting can injure the spine. Instead, rotate your heels and torso while holding a wood chop or medicine ball.

For more tips, check out Women’s Health 10 Exercise Machines to Avoid.

Follow @WTOP on Twitter.

(Copyright 2012 by WTOP. All Rights Reserved.)