Many weight-loss plans include recommendations for strength training, so you gain valuable muscle mass to help with calorie burning. The two to three resistance-training sessions suggested per week for these plans won't turn you into a body builder, but will help you preserve some tone and function as you slim down. If you're still not interested in adding any lean tissue, following a low-calorie diet without participating in any formal exercise will help prevent the addition of muscle mass.
A Calorie Deficit for Weight Loss
To lose weight, you must feed your body fewer calories than you burn. Formal exercise helps you burn more calories to make creation of this deficit easier, but it also builds muscle. To avoid gaining muscle, you'll have to create the bulk of your deficit by just eating fewer calories.
Determine how many calories you need daily to maintain your weight. Use an online calculator that accounts for your age, gender, size and activity level. The average sedentary adult needs between 1,600 and 2,600 calories per day, depending on gender and size. Larger, younger men tend to burn more calories than smaller, older women.
From that maintenance number, subtract 250 to 1,000 calories daily to lose 1/2 to 2 pounds per week. If you don't exercise, you may need to settle for a low rate of loss. Do not follow a plan that contains fewer than 1,200 calories per day for a woman, or about 1,600 for a man, or you risk becoming nutritionally deficient and stalling your metabolism. Very low calorie intakes should only be followed for a medically prescribed plan.
Too low of a calorie intake will also lead to quick loss of lean muscle mass. You may not want to gain muscle, but losing muscle diminishes your metabolism and makes weight loss harder.
Dietary Strategies to Lose Weight
Your initial step in creating a weight-loss plan is to cut out all the "extra" calories that offer little in the way of nutrients. Minimize sugary sweets -- especially baked goods and soda -- processed snack foods, and saturated fats found in fatty meat and full-fat dairy. Depending on how much of these foods you eat, cutting them out may help you save enough calories to start losing weight.
Eat moderate portions of healthy, whole foods to support your weight-loss efforts and enable your body to obtain an array of nutrients. Plan on consuming a variety of fresh vegetables at each meal, as well as a lean protein at meals, and sometimes at snacks, to curb hunger and provide essential amino acids. Examples include fish, white-meat poultry and tofu. You want a to eat a minimum of 0.36 grams of protein per pound of body weight daily. Moderate portions of healthy fats such as olive oil and nuts provide essential fats. Whole grains, including brown rice and 100 percent whole-wheat bread, are also important to include in your meals, since carbs are a primary source of energy for your body. Skip the cereal bars and packaged diet "shakes." Instead, snack on whole foods such as fresh fruits, low-fat cheese and woven wheat crackers, or low-fat, plain yogurt with berries.
Perform Non-Muscle-Building Physical Activity
Participating in no physical activity whatsoever compromises your long-term health. Even if you don't want to build muscle mass, do the weekly 150 minutes of moderate-intensity cardio activity recommended by the Centers for Disease Control and Prevention. This amounts to a brisk walk of about 3 mph for 30 minutes, five times per week. This modest workout helps you decrease your risk of heart disease, type 2 diabetes and some cancers.
Even if you're not interested in building muscle mass, some muscle-strengthening activity is important to maintain the muscle you do have. Strength-building exercise also has other benefits, including improved bone health and better posture, which makes you look thinner. Yoga and gardening count as muscle-strengtheners, according to the CDC. Preserve muscle to ensure you can still perform simple activities during the day, such as carrying grocery bags, and foster joint health. As you age, you naturally lose muscle mass if you don't actively maintain it through activity. This puts you at risk for falls and may compromise your independence.
Increasing Your Calorie Burn
Your body burns calories to just function every day. You need a certain amount to run bodily functions, such as pumping blood, and for digestion. It's hard to alter this basal metabolic rate in any significant way without adding muscle.
Activities common to daily life, such as showering and cooking dinner, also burn calories. To burn more calories without adding notable muscle, you could increase these non-exercise thermogenic activities, or NEAT. Pace while you're on the phone, take the stairs instead of the elevator, or park farther away from your destination. Even just fidgeting and walking often during the day helps you in your quest to drop pounds.