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BMI - body mass index

10 Reasons Why Lean Body Mass is Important

  blog post author icon   blog post published date icon   09/20/21

Exercise  Weight Loss  

One of the best ways to reduce fat and stay healthy is to build lean body mass. As we age, our muscle mass starts to decline rapidly, leading to physical and cognitive deterioration. Due to the rapid decline in muscle mass, most of us begin to gain fat easier as we age.

  • Blog Post

    Obesity affects 42% of the USA's population, and its prevalence is detrimental to our long-term physical and mental health.

    You may be thinking, why should I get lean, isn't being lean just for bodybuilders? The answer to that is no. We all need to build muscle and keep our bodies strong to ensure the longevity of good health. 

    Why is lean body mass important, and how do you build lean body mass to stay healthy? Keep reading to find out the answers.

    What Is Lean Body Mass?

    In simple terms, lean body mass is your body weight minus your fat mass.

    Lean body mass is how much you weigh when the fat is not counted. Lean body mass includes the weight of your body water, your skin, bones, muscles, ligaments, and tendons.

    Lean body mass is critical because it benefits your overall health and ability to maintain a healthy weight.

    What Is Muscle Mass?

    Muscle mass is a different measurement to lean body mass; it is the weight of your muscles only.

    Maintaining a healthy muscle mass goes hand in hand with maintaining a lean body mass. As you strengthen your muscles, they grow. The stronger your muscles, the faster they can burn fat and calories. This, in turn, leads to a better lean body mass.

    When you have a healthy amount of muscle mass, you will not only feel stronger but will contribute to improved metabolism and fat loss.

    Healthy muscle mass percentages vary by age and depend on whether you are a man or woman.


    Healthy muscle mass percentages depend on your age. The average muscle mass for men depending on age should be:

    • Age 36-55: muscle mass should be 36-40
    • Age 56-75: muscle mass should be 32-35
    • Age 76-85: muscle mass should be <31


    For women, the healthy ranges for muscle mass are:

    • Age 36-55: muscle mass should be 29-31
    • Age 56-75: muscle mass should be 27-30
    • Age 76-85: muscle mass should be <26

    Remember that muscle mass and lean body mass are different. These numbers are purely for the percentage of your weight that should be muscle.

    Here are more reasons you should maintain a high lean body mass.

    1. Improves Your Fitness

    When you train regularly, you burn fat and build muscle. This contributes to your fitness levels and strengthens your muscles. The more you get used to strength training, the easier your body will adapt and grow new muscles.

    By reducing your fat mass and increasing your lean body mass, you will become much fitter. As you get fitter, you will be able to partake in physical activities you may not have done before. 

    2. Boosts Your Metabolism 

    As a general rule, the higher your lean body mass, the higher your basic metabolic rate (BMR).

    Your basic metabolic rate is vital for burning calories while you aren't active. 10lb of muscle burns 50 calories when you rest, whereas 10lbs of fat only burns 20 calories.

    A healthy metabolic rate is essential for maintaining a healthy weight, as is not consuming more calories than you burn in a day.

    Physical activity can also increase your metabolic rate. When you work to maintain your lean body mass, you will need to increase your physical activity.

    3. High Lean Body Mass Can Prevent Obesity

    The rate at which you burn calories while resting is crucial for avoiding obesity. If you have a high muscle mass, you burn more fat and are less likely to have calorie imbalances that cause weight gain. 

    Lean muscle makes your metabolism work harder and makes you less likely to store fat.

    4. Strengthens Your Bones

    When you have a high lean body mass, it is usually a consequence of working out and strength training. 

    How to get lean? By training your muscles. Regular strength training coincides with improved bone density. When your bones become stressed through resistance training, it stimulates them to become stronger.

    Resistance training is one of the best things you can do to reduce the loss of bone density that occurs as we age.

    5. Can Fight Disease

    Obesity can be the cause of many chronic diseases such as heart disease and various cancers.

    When you have a high lean body mass, you are less likely to be obese. This reduces your chances of developing chronic disease.

    If you have a high muscle mass, it can also help you fight illness. The immune system needs proteins to fight off disease. Your immune system will use the protein from your muscles to help you heal and recover.

    Thus, maintaining high muscle mass works wonders for your recovery time if you get sick.

    6. Promotes Longevity

    Maintaining a high lean body mass helps slow the process of aging. As mentioned, your bone density and muscle mass gradually deteriorate as you get older.

    If you maintain a healthy lean body mass and high muscle mass, you can fight off many ailments associated with aging, such as brittle bones.

    7. Helps Joint Health

    When you strengthen the muscles around your joints, it can take the pressure off the joint. This can result in less joint pain and healthier joints.

    There is a link between low lean body mass and arthritis. Those with lower lean body mass are more likely to gain arthritis.

    8. Gives You a Healthier Heart

    Why is muscle mass important? It is the main contributor to fat loss and lean body mass.

    To achieve a healthy muscle mass, you need to exercise. This helps to strengthen one of the strongest muscles in your body; your heart.

    The healthier your heart, the more likely you are to maintain overall health, longevity and help you ward off heart attacks and strokes.

    9. Makes You More Confident

    When you have less body fat and more lean muscle, it can boost your self-confidence and mental wellbeing. When you can walk up the stairs without getting out of breath, carry something heavy or go for a long walk with ease, it improves your overall quality of life.

    A weak body can often impact your state of mind and cause stress as you can't do many of the things that make you happy.

    10. Makes You Stronger

    When you have a healthy lean body mass, you will feel physically stronger. Your body's resistance will improve, as will its ability to ward off disease,  infection, and chronic illness.

    You will have more endurance and be able to take on new challenges, both physical and mental.

    How to Measure Lean Body Mass

    You can measure lean body mass by first finding out your fat mass. You can determine fat mass by using a fat mass scale. These special scales calculate how much fat your body is storing.

    If you don't have fat mass scales at home, you can check your local gym. This is a pretty standard piece of equipment in gyms.

    Remember the calculation to find out your lean body mass is:

    Total weight - Fat mass

    Completing this simple calculation will show you what your lean body mass is.

    To measure solely muscle mass without water, bones and organs is a little more complicated as you need a specialized scale. Your gym or doctor may have such a scale.

    How to Maintain Lean Body Mass

    The best way to maintain your lean body mass is through strength and resistance training.

    You can do bodyweight resistance workouts such as push-ups or squats; you may choose to lift weights or do some yoga. You don't need to go to a gym to stay fit; you can do some of these easy at-home exercises.

    Try to get at least 150 minutes of moderate intensity exercise per week.

    Combining your training with a healthy diet is also essential. To build lean muscle, you need adequate protein, fiber, and vitamins. Eat a rich and varied diet that includes an abundance of fruit and vegetables and little saturated fat.

    You can also get leaner by using supplements for your diet. Supplements can help you get the nutrients for muscle growth and fat loss that your diet lacks.

    Prolong Good Health With Lean Body Mass

    As you've learned, lean body mass is essential for just about every aspect of our health and wellbeing.

    Maintaining lean body mass goes hand in hand with muscle mass and ensuring you have strong, healthy muscles. Having zero body fat doesn't equate to good health, especially if it means you don't have any muscle mass.

    Maintaining muscle mass and thus lean body mass doesn't have to be hard.

    Incorporating simple changes into your everyday life, such as strength and resistance training along with a healthy, balanced diet, can improve your lean body mass.

    If you want to learn more about developing healthy habits, try out our online education courses on health and wellbeing.

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