The 5 Best Machines for Women

You can bump up your metabolism by nearly 20 percent for at least two hours after your workout.

Studies show that circuit training twice a week may lower blood pressure and improve cardiovascular health.

It'll put you in a better mood. One recent study found that women who regularly lifted weights felt healthier and had a more positive body image.

lean, sexy body!

Don't forget to adjust the machines to fit your body. Keeping the seat too high or too low or placing your hands or feet in the wrong position not only makes the exercise less effective, but it can also put you at risk for injury.

Don't focus only on problem spots. Concentrating on just your butt, abs, or thighs and ignoring areas like your back, chest, or hips will make your body look imbalanced while also setting you up for injuries.

Don't work too hard. If your arms are so sore you can't hug your pillow, or if your quads ache for days going down a flight of stairs, it's time to back off and go with either fewer reps or less resistance.

Don't do the same routine for more than a month at a time. Your muscles will be as bored as your mind — and you'll stop seeing results. Surprise your body by adding a new exercise at least every four weeks.