In just over a year I have lost 30 pounds by working out six times a week and watching my diet, but now I'm stuck. How can I start losing again?

First, let me congratulate you on your great success. It sounds like you followed a sensible program. Sticking to a routine six days a week takes real dedication. Now that your body is more efficient and you've reached a plateau (which is normal), it's time to shake things up.

If you're performing 12 to 15 repetitions of each exercise, add weight and do fewer reps. If you do 45 minutes of cardiovascular exercise, shorten some workouts by 15 minutes and work harder. On other days, add 15 minutes and go slower to extend your exercise time. Increase your overall intensity, and allow yourself a day off sometime. You can exercise five days one week and six the next. I can't be more specific, because I don't know your routine.

Over the past year, you've challenged your body with the stimulus of exercise. Your muscles have gotten stronger, your heart and lungs work more efficiently, and your body has used up fat stores to make up the calorie deficit you create with exercise and diet modification. All of your systems are coasting and need new challenges to click back on, like the thermostat of a cooling system.

For instance, don't just vary the length and intensity of your aerobic sessions -- change them. If you have been using the treadmill for 45 minutes, try the stepper for 30 minutes one day and the stationary bike on another. Extend your treadmill session beyond one hour -- or better yet, walk or skate outside.

Practically speaking, adding more lean mass to your frame will help you burn more calories at rest. Extending some of your cardiovascular sessions will burn more calories. Remember: Variety is the spice of life. Change is good.

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