What is Skeletal Muscle? Its Functions, Benefits and Calculations

Having a body that not only looks toned but also full of energy and supports you in every movement you make sounds like a dream, right ladies? 

We all want to experience this, yet, in reality, most of us face difficulty in carrying out routine tasks. Our energy levels decline with age, and we feel tired most of the time. It happens because of women’s muscle mass loss and other such changes. 

The good news? By understanding and learning about skeletal muscle mass for women, its functions, health benefits, and ways to build muscle mass, you can transform your fitness journey. 

Continue reading to know more!

What is Skeletal Muscle? 

30 to 40% of our total body mass is composed of voluntary skeletal muscles, meaning their movements are under your control. Also, skeletal muscles are connected to your bones and allow you to perform different ranges of movements. 

Tough bands of connective tissue called tendons attach skeletal tissues to bones throughout the body. Here are some of the examples of skeletal muscles: 

• Shoulder muscles 
• Abdominal muscles 
• Hamstring muscles 

Importance of Understanding Skeletal Muscle Mass for Women 

An appropriate ratio of skeletal muscle mass for women is highly important as it greatly impacts their health, fitness and quality of life. 

Here’s how it impacts women’s lives:

• Muscle tissue burns more calories at rest than fat tissues. So, having higher muscle mass helps women to maintain healthy body weight. 
• Research states that skeletal muscle is essential for glucose clearance and uptake. It enhances glucose uptake and storage, reducing the risk of insulin resistance and type 2 diabetes.
• Besides, women are at higher risk of sarcopenia (age-related muscle mass). Building healthy muscles can help women age well and delay the onset of sarcopenia.
• Menopause leads to hormonal changes and can accelerate muscle mass. However, building and maintaining muscle mass through lifestyle modifications can help women to counteract these changes.

Discover the ideal muscle mass for women by using our muscle mass percentage calculator. 

Functions and Anatomy of Skeletal Muscle in Women 

Skeletal muscles, along with cardiac and smooth muscles, play a part in almost every body function. Research states skeletal muscles contain nearly 50 to 70% of all body proteins.

Women’s muscle mass is equally important to men’s muscle mass and helps them execute bodily functions smoothly. 

Basic functions like enabling movement, metabolic health, vision, and posture are the same for both genders. Let’s have a look at these functions:

1. Mobility 

Skeletal muscles work in conjunction with bones and joints to move. They are responsible for all voluntary movements, including running, jumping, walking and dancing.

What’s more? The muscles in your hands and fingers also help you carry out the precise movement required for activities like sewing, playing musical instruments, and typing.

2. Posture 

Skeletal muscles help to maintain posture by stabilising your joints and spine. This way, they maintain an upright position against gravity. Not to mention that strong postural muscles help maintain balance and reduce the risk of falls, especially as women age.

3. Vision 

Six skeletal muscles are present in your eye sockets, which help you move your eyes. The internal muscles of your eyes contain smooth muscles. All these muscles work together and help you see the things around you. 

4. Metabolic Functions 

Muscle tissues are efficient in burning calories and help to lose weight faster. That’s why women who are conscious about their weight and want to get a leaner and toned look should build healthy muscle mass.

5. Enhance Bone Density 

Women are at a higher risk of osteoporosis, which has a negative impact on the emotional, physical and mental well-being of postmenopausal women. Building skeletal muscle mass for women  can increase bone density and stronger bones helps to delay the onset of diseases like osteoprosis. 

6. Anatomy of Skeletal Muscles

Skeletal muscles are present throughout the body and divided into categories depending on their location and function. 

Where Are Skeletal Muscles Located? 

Here’s a general overview of the location of skeletal muscles: 

1. Head and Neck 

• Facial Muscles: Control facial expressions (e.g., orbicularis oris, orbicularis oculi)
• Masticatory Muscles: Helps in chewing (e.g., temporalis, masseter)
• Neck Muscles: Involved in head movements and swelling (e.g., trapezius, sternocleidomastoid)

2. Upper Body 

• Shoulder Muscles: Control shoulder movements (e.g., rotator cuff muscles)
• Arm Muscles: Involved in arm and hand movements (e.g., triceps brachii, biceps brachii)
• Chest Muscles: Assist in arm and shoulder movements (e.g., pectoralis major, pectoralis minor)

3. Trunk 

• Abdominal Muscles: Support trunk movements and posture (e.g., obliques, rectus abdominis)
• Back Muscles: Stabilize and move the spine (e.g., erector spinae, latissimus dorsi)

4. Lower Body 

• Hip Muscles: Control hip movements (e.g., gluteus minimus, gluteus maximus)
• Thigh Muscles: Involved in hip and knee movements (e.g., quadriceps, hamstrings)
• Leg Muscles: Assist in toe and foot movements (tibialis anterior, soleus)

Properties of Skeletal Muscles :

Skeletal muscles are extensible, which means they can easily extend when stretched. Also, they have elasticity and can return to their original structure when released. They respond after coming in contact with a stimulus. Besides, skeletal muscles have contractility, meaning they can contract after coming in contact with a stimulus.

Structure of Skeletal Muscles 

Skeletal muscles are attached to the bones through tendons, which are collagen fibres or elastic tissue. 

Each muscle looks like a well-organized bundle of long cylindrical cells called muscle fibres that are like tiny threads and all neatly packed together. Furthermore, each muscle fibre is surrounded by a thin layer of connective tissue called the endomysium. 

Now, these muscles don’t just float around; they are further organised into a bundle called fascicles. 

Each fascicle is wrapped in another layer of connective tissue called the perimysium. Inside each muscle fibre, you’ll find even smaller structures called myofibrils, which are the real powerhouse of the muscles. 

Myofibrils are packed with repeating units called sarcomeres (the smallest functional units responsible for muscle contraction). Proteins like actin and myosin are present inside sarcomeres that slide past each other to make the muscle contract. 

The entire muscles and all these bundles of fascicles are held together in a tough layer called epimysium. 

Blood vessels and nerves pass through these layers, ensuring each muscle gets the nutrients, oxygen, and signals for proper functioning. 

How do Skeletal Muscles Work in the Female & Male Body? 

Women and men have differences in muscle mass distribution, hormonal profiles, and physiological responses, which is why some characteristics of skeletal muscle mass vary. 

Here are the key distinguishing functions of women’s muscle mass from men: 

Average Muscle Mass Percentages for Women 

Muscle mass percentages for women and men are different. This difference is largely due to hormonal variations.  According to research, testosterone increases muscle mass by increasing protein synthesis.

Women have low levels of testosterone, which influences muscle growth. Understanding how to build skeletal muscle mass for women can transform your fitness journey. 

Below, we have mentioned the average muscle mass percentages for women according to their age: 

Muscle mass percentage simply refers to the proportion of your body that is made up of muscles.  The average muscle mass for women ranges from 30 to 40%, while for men, it’s usually between 40-50%. 

Muscle mass impacts your strength, metabolism and overall energy levels. Read this blog to learn more about the impact of muscle mass on your overall health. 

Average Muscle Mass for Women: What’s Normal? 

Muscle mass percentage in women varies according to age, diet, and activity levels. As women age, muscle mass tends to decline and may even lead to sarcopenia. That’s why they need to stay active and eat well. 

Source: A Study by the Journal of Applied Physiology

7 Key Factors Affecting Muscle Mass Percentage in Women 

Here are the main factors that affect women’s muscle mass:

1. Age 
   • Young women have higher muscle mass due to the higher level of anabolic hormones (synthetic hormones that help grow and repair muscle tissue). 
   • Muscle mass and strength decline with age, especially after age 30, due to hormonal changes and reduced physical activity. 
2. Physical Activity Level
   • Regular resistance training stimulates muscle protein synthesis and promotes muscle growth. 
   • Similarly, women who are not physically active are more prone to gaining weight and low muscle mass.
3. Hormones
   • Estrogen has anti-inflammatory properties and helps in muscle repair, recovery and maintenance. 
   • As women reach the stages of menopause, the estrogen level decreases, resulting in low muscle mass and strength.
4. Nutrition
   • A well-balanced diet containing all the nutrients supports muscle growth. Especially, those women who exercise regularly should consume a protein-rich diet. 
   • Protein helps in muscle repair and growth, carbohydrates provide the necessary energy for workouts and fats are needed for hormone production. 
5. Genetics 
   • Genetics also play an essential role in determining muscle mass potential, muscle fibre type distribution and response to training. 
   • Some women naturally have more fast-twitch muscle fibres, while others may have more slow-twitch fibres. Remember, fast-twitch muscle fibres are more responsible for muscular hypertrophy (an increase in muscle mass). 
6. Lifestyle
   • Proper sleep is needed for muscle recovery and growth. Similarly, poor sleep can negatively affect muscle protein synthesis and recovery from workouts. 
   • Chronic stress can increase cortisol levels, promoting muscle breakdown and inhibiting muscle growth. 
7. Medical Conditions
   • Certain medical conditions like hypothyroidism and chronic illness can affect muscle mass. 
   • Also, medications like corticosteroids can decrease muscle mass when used for a long time. 

Benefits of Maintaining Healthy Skeletal Muscle Mass for Women 

Let’s have a look at the research-based benefits of muscle mass for women:

1. Physical Health Benefits 

Skeletal muscle is metabolically active which can burn calories faster than fat, even at rest. Women with high muscle mass have improved metabolism and strength. Also, stronger muscles make it easy for women to perform daily tasks like climbing stairs or running around with the kids. 

According to research, resistance training increases bone mineral density in premenopausal women. When your bones are strong, the risk of falls and osteoporosis is highly reduced. Maintaining skeletal muscle mass for women becomes more important as they age since it helps prevent muscle loss and deterioration. 

2. Mental Health and Skeletal Muscle Mass 

To build muscle mass, exercise regularly, particularly strength training. Such activities release endorphins, which can improve your mood and reduce the symptoms of depression. Besides, regular physical activity regulates hormones like cortisol and keeps stress at bay. A study found that strength training improves sleep quality and reduces the symptoms of depression among patients with diagnosed depression.

Building muscles also leads to better body image and increased self-esteem in women. 

3. Long-term Benefits for Women Aged 20-35 

Increased muscle mass is linked with improved insulin sensitivity and reduces the risk of type 2 diabetes. Also, maintaining lean body mass women is essential for metabolic health, especially as you age. Research proves that higher muscle mass is associated with improved insulin sensitivity and a lower risk of diabetes.

Furthermore, strong muscles also contribute to improved mobility and independence in older people. 

How to Calculate Skeletal Muscle Mass?

You can determine muscle mass by using the different formulas and methods which we have discussed below:

Simple Estimation Formulas for Skeletal Muscle Mass 

To use these formulas, you need to know the basic information like height, weight and age. Here are the details of these formulas: 

1. Fat-Free Mass Index (FFMI)

This is the ratio of your muscle mass to your height: 

FFMI = Fat-Free Mass (Kg) / Height (m)^2

To estimate your fat-free mass, you can simply subtract your fat weight from your total weight.

You can use: Lady fitness website for the free calculator  

2. The Hume Formula 

Hume formula helps to estimate your lean body mass (everything in your body except fat): 

Lean Body Mass (kg) = (0.3281 × Weight (kg) ) + 0.33929 × Height (cm) ) – 29.5336 

3. Bioelectrical Impedance Analysis (BIA)

BIA involves devices like specific bathroom scales that send a tiny electrical current through your body to estimate muscle mass. 

No math is needed; just step on the scale, and you will get your estimated muscle mass. 

Tools and Methods for Measuring Muscle Mass in Women 

The following methods and tools come in handy in measuring muscle mass: 

• Ultrasound 
• Skinfold Measurements 
• Computed Tomography (CT) Scans 
• Magnetic Resonance Imaging (MRI) 
• Hydrostatic Weighing (Underwater Weighing) 

Each method has its pros, cons and specifications. You can learn the details of these methods here. Calculate your average muscle mass for women and set realistic goals for building a leaner and toned physique. 

How to Calculate Your Lean Muscle Mass and Lean Body Mass? 

Lean body mass is also known as ‘Fat-free Mass’. It includes the body’s weight of bones, organs, and muscles. For calculating the lean body mass, you can use the below-mentioned equation: 

Lean Body Mass = Total Body Weight – Fat Mass 

Here, we first need to calculate fat mass, and this can be done by using the following formula: 

Body Fat Mass = (Body Fat Percentage / 100) × Total Body Weight 

You can measure the body fat percentage using tools like skinfold callipers, BIA devices or advanced methods like DEXA scans. 

Example: 

Suppose the total body weight of a person is 70 kg and her body fat percentage is 25%. Let’s put these values into the formulas: 

Body Fat Mass = (25/100) × 70 = 17.5 kg 

Lean Body Mass = 70 kg -17.5 kg = 52.5 kg 

Tips for Maintaining and Increasing Skeletal Muscle Mass 

Increasing skeletal muscle mass for women not only shapes a toned physique but also supports long-term weight management. To support muscle growth, follow the below-mentioned tips: 

1. Nutrition Tips for Muscle Growth 

Aim for 1.6-2.2 grams of protein per kilogram of your body weight daily. Lean meats, dairy and legumes are good sources of protein. You can use our protein calculator to know your daily protein requirements according to your age and body composition. 

Consume 3-5 grams of carbohydrates per kilogram of body weight from whole grains, fruits and vegetables for getting enough energy and glycogen replenishment. 

Make sure to take at least 20-35% of calories from healthy fat sources like fatty fish and avocados to support hormone production. 

Don’t forget to stay hydrated and drink at least 8-10 cups of water daily. 

2. Effective Workouts for Women to Build Muscle Mass 

Regular exercise is highly important for building muscle mass. Start small so your body can adapt. 

Here is the list of workouts which you can do to build muscle mass: 

• Squats 
• Pkanks 
• Push-Ups 
• Tricep dips 
• Russian twists
• Shoulder press 
• Bent-Over rows 

Achieving a healthy muscular women weight requires a balance of strength training and proper nutrition. 

Conclusion 

Skeletal muscles are one of the three types of muscle tissues and work in conjunction with other muscles to perform different body functions. They are responsible for various body movements like writing, typing, extending an arm, walking, running, etc. 

Muscle mass for women varies depending on various factors like age, genetics, diet and physical activity level. Lower muscle mass can lead to age-related issues like sarcopenia, while higher muscle mass is associated with longevity. 

Building skeletal muscle mass for women is essential for enhancing strength and boosting metabolic rate. 

Regular resistance training and a well-balanced diet can help women to build muscle mass. Want to know how? Read our blogs and let us help you get the strength through science, not hype. 

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