Strength training -- also called resistance training or, simply, weightlifting -- isn't just for those muscular bodybuilders at the gym.

It's a type of exercise that should be part of everyone's overall fitness plan. Why? Strength training keeps muscle toned, reduces body fat, and helps burn more calories even when you're not working out.

Strong muscles are especially important as you age to stay steady on your feet and as independent as possible. A study published in the Journal of Physical Therapy Science found that a simple lower body strength and balance training program can decrease falls as you get older. Upper body strength counts, too, allowing you to accomplish everyday tasks, from carrying groceries to walking your dog.

If you're new to strength training, a certified trainer can put together a plan with your fitness goals and ability in mind. Look for qualified professionals on the American Council on Exercise's website.

You don't have to join a gym to strength train. You can work out at home using a set of free weights, such as a mix of dumbbells and barbells; a home weight-training machine; resistance bands that come in graduated tensions; or even plastic bottles filled with sand or water.

Do a total body workout at least twice a week, one that targets all the major muscle groups. An alternative is to break up your routine by focusing on your upper body two days of the week and on your lower body and "core" abdominal muscles on two other days.

As you get stronger, challenge yourself. Whenever an exercise in your current routine gets too easy, add more repetitions or more weight/resistance.

It's important to give your muscles a break, too. Always allow two days between training sessions to give muscles time to recover and grow.