It’s hard to accurately measure muscle mass as it depends on various factors. Though the data is limited, research does provide some insight.
Your body mass is made up of two components: body fat and lean body mass.
People often use the terms “lean body mass” and “muscle mass” interchangeably, but they’re not the same. Lean body mass includesmuscle mass, as well as skin, bone, water, and organ mass.
Muscle mass refers to the weight and size of the smooth muscle tissue in your body. It
Skeletal muscle helps control physical movement and posture. It plays a key role in mobility, balance, and strength, and maintaining muscle mass becomes even more important as you get older.
Keep reading to learn more about muscle mass averages, how much you should aim to have, and how to build muscle mass.
Muscle mass is difficult to measure on its own because it depends on many factors, including height, diet, ethnicity, and fitness level.
There are currently no recommended guidelines on how much muscle mass a person should have. On average, however, skeletal mass makes up
In a 2000 study, researchers measured the muscle mass percentages of 468 adults in different age groups. The following charts are based on this study. While new research is necessary, this data will give you an idea of muscle mass percentages for different age groups.
Muscle mass percentage averages for men
| Age (years) | Muscle mass percentage |
|---|---|
| 18 to 35 | 40% to 44% |
| 36 to 55 | 36% to 40% |
| 56 to 75 | 32% to 35% |
| 76 to 85 | less than 31% |
Muscle mass percentage averages for women
| Age (years) | Muscle mass percentage |
|---|---|
| 18 to 35 | 31% to 33% |
| 36 to 55 | 29% to 31% |
| 56 to 75 | 27% to 30% |
| 76 to 85 | less than 26% |
It’s not possible to determine your exact muscle mass percentage without expensive technology. Some of the possible measurement tools include:
- magnetic resonance imaging (MRI)
- dual-energy X-ray absorptiometry (DEXA)
- computed tomography (CT)
- ultrasound
- bioimpedance analysis
- D3-creatinine dilution
According to a 2020 review, imaging tests are considered the “gold standard” for measuring muscle mass.
However, it’s important to note that different measuring tools can provide varying results when assessing the same person. In a 2023 study that compared the differences between D-creatinine dilution and MRI, researchers found that D-creatinine dilution results varied from 0.62 kilograms (kg) lower to 13.47 kg higher than MRI.
Are there other ways to measure muscle mass?
Healthcare professionals usually measure body composition to determine how much muscle mass you have. Body composition measures the proportion of muscle, fat, bone, and water in your body.
Several measurement tools, formulas, scales, and calculators can be used to assess your body composition at home, in a gym, or in a clinical setting. Some of these may include:
- hydrostatic weighing
- body fat scales
- waist and hip measurements
- skin calipers
- online calculators
These tools are less accurate than medical assessments, but they could give you an idea of how much skeletal mass you have compared to fat, water, and bone mass.
If you want to calculate your muscle mass, speak with a healthcare professional. They could recommend different measurement tools that fit your budget.
In general, healthcare professionals recommend maintaining a higher muscle mass.
As you get older, you naturally begin to lose muscle mass, a process called sarcopenia. This age-related muscle loss most commonly begins at age 40 years, and you may continue to lose up to 8% of muscle mass every decade.
Sarcopenia is
Having low skeletal muscle mass is also associated with several health conditions, including:
- diabetes
- heart disease
- chronic liver disease
- kidney failure
- obesity
- osteoporosis
- complications after surgery
- increased risk of early mortality
Maintaining and building muscle mass is key to improving overall metabolism, protecting physical ability, and improving the quality and longevity of life.
Some research suggests that maintaining higher muscle mass, strength, and function may also have psychological and cognitive benefits. However, more research is needed to fully examine this link.
What are the downsides of having higher muscle mass?
If you have higher-than-average muscle mass, it may be difficult to find clothes that fit well. You’ll also need to eat more calories to feel full, which can become inconvenient and expensive.
Some people also report that greater muscle mass reduces their flexibility and ability to jump or run. However, these are variables that you can work on at home or in the gym, either alone or with a personal trainer.
Exercise and good nutrition are two key components of building muscle mass and preserving it as you age.
Exercise
Strength training — also known as resistance or weight training — is one of the most effective ways to build muscle mass. This type of exercise strengthens your muscles by forcing them to work against resistance.
You can:
- do bodyweight exercises, like pushups
- do resistance band exercises
- lift free weights, like dumbbells or soup cans
- use weight machines
- do high intensity interval training (HIIT)
- do Pilates
The
If you’re not sure where to begin with exercising for muscle mass building, speak with a doctor or a personal trainer. They could help develop an exercise program for you.
Diet
Eating a nutrient-dense, balanced diet is also key to gaining and maintaining muscle mass. Good nutrition can help fuel your body and repair muscle after exercise.
Protein, which helps build and repair muscle, is particularly important. The amount of protein you need depends on your level of physical activity, but
Examples of high protein foods include:
- beef
- poultry
- fish
- eggs
- beans
- nuts
Eating carbohydrates can also help fuel your muscles, especially if you’re performing more than 10 exercise sets per muscle group during a workout. It’s important to choose complex, high fiber carbs rather than refined or ultra-processed carbs.
Additionally, adequate intake of fat, vitamins, and minerals is necessary for building muscle.
It’s also best to limit ultra-processed foods as much as possible. By eating whole foods, like vegetables and eggs, you can help your muscles stay healthy and strong.
Muscle mass is a part of your lean body mass. Typically, the more muscle you have, the less prone you are to injury, chronic disease, and early death. Muscle mass also indicates physical function, including mobility and balance.
It’s difficult to calculate lean body mass, let alone muscle mass. The most accurate methods are expensive, and there isn’t a lot of reliable data proving their accuracy.
To better understand your physical fitness, it’s recommended to use your body fat percentage instead.