How to Improve Body Composition With Nutrition and Exercise

Improving your body composition has many health benefits and is also often a goal of those seeking to change their physical appearance. Some people make drastic changes to their body composition for physique and bodybuilding shows, while others simply wish to make lasting changes to their body fat and muscle mass.

Sustainable, long-term body composition changes start with health-focused dietary and exercise habits that support overall well-being and fitness. Learn more about body composition and how you can improve it below.

What Is Body Composition?

Body composition describes the percentages of fat, bone, muscle, water, and other tissues in the body. Most often, body fat and muscle percentage are the primary focus of people looking to understand or improve their body composition.

Your lean body mass is your total body weight minus your body fat weight, otherwise known as fat-free mass. Lean body mass is often mistaken as referring to muscle mass alone, but it actually refers to any tissues in your body that are not fat mass (adipose tissue). This includes muscle, bone, organs, nerves, hair, nails, ligaments, tendons, etc.

Keeping your body fat levels within a healthy range reduces the risks of all-cause mortality. As well, low levels of lean body mass, such as muscle and bone, increase your risks of all-cause mortality. Having excess body fat may put you at risk of developing heart disease, metabolic syndrome, high blood pressure, or type 2 diabetes.

How Do You Improve Body Composition?

Improving your current body composition requires changes to your diet and exercise habits. Other factors may contribute as well, such as sleep, hormones, and stress levels.

Nutrition and Body Composition

The foods you consume can affect your body composition, including how much muscle, water, bone, and body fat you have. Body mass is synonymous with weight, so the theoretical "improving" of body composition is very subjective. If you're looking to "improve your body composition"—whatever that means for you—increasing muscle mass, decreasing fat mass, or weight loss or weight gain may be indicated.

In very simplistic terms, weight is dictated by whether you consume the same, more, or fewer calories as you burn. Consuming more calories results in weight gain, fewer calories lead to weight loss, and the same calorie intake as output will maintain your weight. However, whether you gain or lose that weight from mostly fat or lean mass depends significantly on your dietary habits.

If weight loss is your goal, research shows that protein intake is the most significant factor in where your weight loss will come from. Consuming a high-protein diet during weight loss will help preserve your muscle tissue, improving your body composition by helping you reduce fat while keeping your lean mass.

Research varies, but consuming 25–30% of your calories from protein may support weight loss better than low-protein diets. If you are active, which you likely will be if you want to make body composition changes, more protein is needed to support your activity and recovery. Aim for a range of 1.2 to 2.0 grams of protein per kilogram of body weight per day, depending on your training, according to the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine.

If increasing muscle mass is your goal, you will likely need to increase overall caloric intake as well as protein. Adjusting your diet to support muscle gain means consuming more calories than you burn and ensuring you get enough protein and carbohydrates to support your training, recovery, and muscle growth while also including enough healthy fats for optimal hormone functioning and health.

If weight gain is your goal, you will also need to increase caloric intake. This can mirror the same method as increasing muscle mass, focusing on nutrient-dense carbohydrate, fat, and protein sources to meet, and generally exceed, your needs.

Exercise and Body Composition

Exercise is how you can make the most noticeable changes to your body composition by increasing muscle mass. Exercise, in general, has been shown to increase lean mass in normal-fat individuals and reduce fat mass in overfat and obese adults. Lowering fat mass and building or maintaining lean mass will improve body composition.

Research shows that adults with excess body fat may particularly benefit from resistance exercise. Studies show that resistance exercise affects lean and fat mass percentages, whereas aerobic exercise only affects fat mass.

Other Factors

Sleep, stress, and hormonal factors interplay to impact body composition as well. For instance, a lack of sleep can impact your hormones, including those that control feelings of hunger and cravings. This could get in the way of your body getting the nutrients it's craving.

As well, without energizing sleep, you'll likely move less and not perform as well during your workouts. Recovery from training will also suffer, impeding muscle gain and fat loss results. Growth hormone is released while you sleep and impacts your muscle mass growth and loss of fat mass. If you do not get enough sleep, your growth hormone levels may not be optimal.

Some people have hormonal shifts that will make fat loss or muscle gain more difficult. Hormone abnormalities such as PCOS or the reduced levels of testosterone and estrogen that come with age and menopause can significantly impact your results.

Similarly, stress can impact food choices, sleep, hormones, and more to make fat loss or muscle gain more challenging. Cortisol, which is a stress hormone, is considered to be catabolic (muscle wasting) and will make anabolism—muscle growth—difficult if it gets too high for too long.

Implementing stress reduction and sleep-promoting practices into your lifestyle will help you counteract these effects. Some people require a substantial break from calorie deficits and intense training to help their bodies relax and de-stress. To address serious issues with stress and hormone levels, it's best to seek guidance from a healthcare professional.

Exercises That Could Impact Body Composition

Cardio Exercise for Body Composition

When it comes to cardiovascular exercise, you can choose whatever form you enjoy. Research shows no difference in weight, fat, and visceral loss between aerobic and high‐intensity interval training as long as energy expenditure was equal. This means so long as your calorie burn is the same, you will get the same results whether performing HIIT or steady-state cardio, so choosing whatever you prefer and can be consistent with will work best.

Strength Workouts for Body Composition

If you are eating correctly to support muscle gain, then performing resistance-based exercises will help you build more lean mass. If you are new to resistance training, you may even see increases in muscle mass while eating maintenance or even deficit calories.

Strength training also helps prevent the loss of lean mass, including muscle tissue, while in a calorie deficit. Types of resistance training range from bodyweight movements to heavy weight lifting. If your goal is to build muscle size, follow best practices for hypertrophy-based strength training by using progressive overload, adding volume consistently over time, and managing fatigue with deload phases. It's also key to track your progress, so you know when to make adjustments to keep on track toward your body composition goals.

How to Put Together a Workout to Improve Body Composition

To put together an effective workout plan to improve your body composition, begin with a minimum of two weekly strength training sessions for each major muscle group. If you have the time, splitting your workouts into 3 to 4 strength training sessions per week will likely be best. Gradually add sets and reps over time to help build muscle mass.

If you enjoy cardio, adding two or more cardio sessions per week will support fat loss, but it will not increase lean mass. Include any cardiovascular activity you prefer. Increasing your overall daily activity through natural movements like walking, climbing stairs, pacing, and taking movement breaks from work will also help you burn more calories if that is your goal.

A Word From Verywell

Changing your body composition is a common goal that can have benefits for your overall health. Focusing on your protein consumption, a balanced exercise routine, and keeping stress levels low all contribute to this change. If you have questions or concerns about your body composition or changing it, it's best to seek advice from a healthcare professional.