Almost everyone hits a plateau while they are dieting. The reasons are many and may relate in part to the fact that the body needs fewer calories than are being eaten or is more efficient at using the calories that are being consumed. An occasional âcheatâ or failure to weigh and measure everything we are eating and drinking may also be behind the stalled diet.. (This assumes that anyone does this for more than three hours at the beginning of the diet.) But one component of the diet program that is often overlooked as contributing to a non-weight loss spell is exerciseâor more accurately its absence . The body adjusts to the smaller number of calories being consumed by slowing down, albeit slightly, its metabolism, or the rate at which calories are being used. Moreover as the body becomes lighter, the caloric cost of moving it becomes smaller. Think about how much effort you have to expend if you are carrying 15 pounds around in a knapsack or in several bags of groceries. Once the knapsack is removed, you can move around using less energy. The same is true when your body is no longer carrying around the 15 pounds you just lost . It needs fewer calories to carry out any type of physical activity and this may account for your weight loss slowing down. There are two ways to get your body to start using more calories so your weight starts to come off again. One is to do calorie-burning aerobic activity and the other is to build calorie-using muscle. Starting an exercise program will immediately increase weight loss. Sometimes it is hard to begin exercising at the same time a diet is begun because there is simply too much to do and too many changes to make. However, once the food plan feels familiar and comfortable, it is important to add physical activity as often, and as long, as possible. My clients often ask me about an exercise schedule. My half-serious answer is that any day they eat, they should try to move. But moving is not enough; building muscle is also very important because as weight is lost, muscle mass is also lost. If someone goes from 250 pounds to 180 pounds, the leg muscles will probably be smaller because there is less trunk weight for the legs to carry. Unfortunately as muscle size decreases, calorie use decreases as well.. Building muscle doesnât require a gym; there are very inexpensive rubber stretchy cords that work well to build muscle, along with books and DVDâs with instructions on how to use them. And keep in mind that if you might have any orthopedic problem from exercising or muscle strengthening, you should get professional help from a physical therapist or knowledgeable personal trainer. But what if you have been doing all this and your weight still stalls? Sometimes the answer is to change your exercise routine. It is possible that your muscles become accustomed to a particular type of physical activity, say walking on a treadmill, and donât have to work as hard as they did when you first began your walking routine. Do something else: For instance, increase the elevation or pace of the treadmill. Go to another machine, such as a bicycle or rowing machine. Walk outside and notice how much harder it is when you are battling wind, walking around mounds of snow or going up and down hills. Change the duration of the exercise. If you have been doing 30 minutes four times a week, then consider doing 60 minutes twice a week. Take classes that have you moving several parts of your body at once, or a class that focuses on strengthening your core, your abdominals, your balance, and your back. Find an event that requires some training so you are motivated to work out longer. If there is a charity walk in the spring that requires walking 15 or 20 miles, in the fall start to increase your mileage on the treadmill or outside so you will be prepared for the walk 5 or 6 months later. Take advantage of seasonal recreational activities to change your physical activity. A day snowshoeing in the winter or kayaking in the warmer months will work out muscles that may be relatively inactive in the gym. If you can find a pool, try water aerobics. It can be exhausting without putting any stress on your body. Finally, try the walking-talking strategy. It is amazing how long we are willing to walk if our conversation is going as quickly as our feet. Find someone with whom you want to have a long conversation, put on a pair of comfortable shoes, pick an interesting route and set out. When you have finished talking, go home. You will amazed at the distance you cover and the weight you will be losing.