How to Lose Fat & Gain Lean Body Mass

Concurrently gaining muscle and losing fat is no easy feat, but can be done with the right exercise and eating routine. When you consistently strength train and increase your protein intake as you cut calories, you create an environment in which your body builds muscle as you shred excess fat. The process takes dedication and effort, but it's worth it to transform your physique and to look and feel healthier.

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Reduce Your Calorie Intake to Lose Fat

You'll need to downsize your calorie intake to lose fat. First, compute the number of calories you need to maintain your weight by using an online calculator that figures in your age, gender, size and activity level. Then, from this number, subtract between 250 and 1,000 calories to create a calorie deficit that yields a 1/2- to 2-pound per week weight loss. Since 3,500 calories theoretically equals a pound of fat, subtracting 500 calories a day from your intake should help you lose a pound a week.

Avoid eating fewer than 1,200 calories per day if you are a woman or 1,800 calories per day if you are a man. Too few calories can lead to muscle loss as your body scrambles to hold onto its fat stores in the face of what it perceives as food shortage. Losing muscle is contrary to your goal of becoming stronger and more defined.

Eat a Diet High in Protein

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To lose fat and gain lean body mass, you need to eat enough protein. A high-protein intake contributes to the preservation and growth of lean muscle when you're reducing calories to lose weight, showed a study in a 2016 issue of the American Journal of Clinical Nutrition. Aim to consume about 0.9 grams per pound of your body weight daily; for a 150-pound person, this amounts to 135 grams spread out over all your meals and snacks.

Research shows that a strategy of increased protein, high-intensity interval training and strength training help you simultaneously build muscle and lose fat. A study published in a 2016 issue of the American Journal of Clinical Nutrition put young men on a low-calorie diet, but increased their protein intake significantly and had them exercise six days per week with resistance and high-intensity intervals. After just four weeks, the participants posted notable increases in lean body mass and decreases in fat mass. Those who consumed the higher-protein diet experienced better results than participants who consumed less protein daily.

Lean meat, fish, eggs, low-fat dairy, poultry and soy are quality sources of protein. For example, 3 ounces of broiled flank steak contains 23 grams of protein; 3 ounces of skinless rotisserie chicken breast contains 24 grams of protein; and 6 ounces of non-fat, plain Greek yogurt contains 17 grams.

Fill the rest of your daily calorie intake with fresh fruits and vegetables, whole grains and unsaturated fats. Keep your intake of sugary treats, refined grains and saturated fats to a minimum.

Strength Train to Gain Lean Body Mass

Strength training helps you maintain lean muscle as you reduce calories and is essential to adding more muscle. If you're brand new to weight training, start out with light weights and just two workouts per week. Do at least one set of eight to 12 repetitions of an exercise to challenge each of the major muscle groups. Options include pushups, pullups, rows, squats, lunges, shoulder presses and hip hinges.

Over time, work up to lifting heavier weights, performing up to six sets per muscle group and a total of six strength workouts per week. Use resistance that feels heavy by the last two to three repetitions in each set. Give yourself at least 48 hours between muscle groups worked to allow for recovery and repair that facilitates muscle growth. Talk to a fitness professional to help you design a program appropriate for you.

Eat Protein After Workouts

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Protein should also feature prominently in your post-workout snack. Consuming a 20-gram serving of protein from whey, meat, soy, eggs or dairy as soon as possible after you strength train promotes muscle growth and repair. Although whole foods are your best options, the International Society of Sports Nutrition notes that you may reach for a protein supplement, such as whey protein powder, because it's convenient and offers an optimal amino acid profile, especially after exercise.

Good post-workout snacks also contain some carbohydrates to restore energy and to further facilitate muscle building. Whole grains, fruits and vegetables are quality sources of carbohydrates. Examples of good post-strength training snacks include half of a turkey sandwich on whole-grain bread with lettuce and tomato; a whey protein shake made with milk and berries; or grilled chicken with brown rice.

Participate in High-Intensity Interval Training

During high-intensity interval training, or HIIT, you alternate bursts of intense cardiovascular exercise with short bouts of lower intensity work. This type of exercise helps you lose fat more effectively than cardiovascular exercise performed at a steady pace, showed a paper published in a 2011 issue in the Journal of Obesity. An example of a 30-minute HIIT workout is warming up on a treadmill for 5 minutes and then alternating 1 minute of all-out sprinting with 1 minute of easy jogging, repeated 10 times. Cool down for the last 5 minutes.

Don't give up completely on steady-state exercise, however. It does help you burn calories and keep your heart healthy, so include it on days between HIIT sessions.