What do you get when you cross an intense weight workout with an equally demanding cardio routine? Circuit training.

This is fast-paced weight training where you move from exercise to exercise -- sometimes running from one to another -- without taking a break.

Many exercises focus primarily on strengthening or cardiovascular activity, but circuit training combines both. You get to build up your muscles and your heart.

Instruction is typically offered in small groups. Each activity is brief, in some cases lasting as little as 15 seconds. Then you move right on to the next station, without resting so you keep burning calories and working your heart.

Activities range from weight machines to exercise bands to dumbbells to calisthenics. There may be several dozen stations, with a session lasting half an hour or so.

• This is a wonderful workout to liven things up if you're feeling stale from doing the same-old, same-old.
  
  
• Circuit training is also the ideal routine if you're short on time.
  
  
• The wide variety and energetic pace prevent boredom.
  
  
• You go at the level of intensity that’s right for you but can still enjoy the motivational aspects of a group setting.
  
  
• Check out a circuit training DVD you can do anytime you feel like burning fat and working up a sweat.

• Although you'll build moderate amounts of strength and burn some calories with circuit training, it's not a pure form of either one.
  
  
• Slower, heavier strength training is better for building strength, and traditional aerobic workouts are better for burning calories and improving your cardiovascular fitness.
  
  
• Depending on the size and speed of the class, an instructor might not have enough time to check each participant’s technique and form thus increasing risk of injury