What is muscle atrophy? Causes, treatments, and exercises

Muscle atrophy is a decrease in muscle mass that can make everyday activities feel more challenging. It often develops gradually with age, or sometimes after an injury or illness that leads to less movement.

“Muscle atrophy happens when your muscles aren’t getting used as much, so they start to lose some strength and size,” says Emily Davis, PT, DPT, a physical therapist at Hinge Health. This can affect things like balance and confidence, and may make you feel less steady or strong during your usual routines.

But muscle strength and function can often be regained. “With gentle, targeted exercises and physical therapy, many people notice real improvements over time,” says Dr. Davis.

Ahead, learn about muscle atrophy, including what causes it, and how to prevent and treat it, especially with exercises recommended by Hinge Health physical therapists.

What is muscle atrophy?

Muscle atrophy means your muscles become smaller or lose some of their mass. “It can happen anywhere in your body, depending on the reason,” says Dr. Davis. You might notice the muscle looks smaller and doesn’t feel as strong as before. 

Types of muscle atrophy  

Muscle atrophy can happen for different reasons. Sometimes it’s due to decreased activity, while aging can also play a role. Common types of muscle atrophy include:

• Muscle loss from inactivity (disuse atrophy): You might’ve heard the phrase “use it or lose it.” Disuse atrophy happens when a muscle or muscles haven’t been used for a while, like if you’ve had a cast on for several weeks, says Dr. Davis. This type of atrophy can be reversed with regular movement and exercise.

• Age-related muscle loss (sarcopenic atrophy): Sarcopenia refers to an age-related decline in muscle and strength. On average, adults lose about 3 to 8% of their muscle mass per decade after age 30. This rate accelerates after age 60, but remember, you can build muscles at any age.

• Muscle loss from nerve problems (neurogenic atrophy): This type of muscle atrophy happens when there’s damage to the nerves that help your muscles work. It can result from conditions like multiple sclerosis, a spinal cord injury, or sometimes type 2 diabetes. “With neurogenic atrophy, it’s more difficult to rebuild muscle mass,” says Dr. Davis. If you notice significant muscle loss with nerve symptoms, it’s important to see a healthcare provider.

• Muscle loss from illness (cachectic atrophy): Also called wasting syndrome, this type of muscle loss happens when the body is under serious stress, such as with certain long-term illnesses. “We see this in people with conditions like heart failure, cancer, or AIDS,” says Dr. Davis.

Causes of muscle atrophy

The causes of muscle atrophy often depend on the type, but common factors include not moving as much, natural changes in hormone levels, not getting enough nutrients (especially protein), and ongoing stress. While some muscle loss is expected with age or after an injury, staying active and taking care of your overall health can help keep your muscles stronger for longer. In some cases, underlying medical conditions can also play a role.

• Physical inactivity. It’s normal to experience some muscle loss after an injury, illness, or when life gets especially busy. Being mostly sedentary can also lead to muscle atrophy, says Dr. Davis. 

• Lower hormone levels. Decreases in hormones like estrogen and testosterone can contribute to muscle atrophy. “Women tend to notice more muscle loss starting around age 50, often during perimenopause,” says Dr. Davis. Men usually see this begin a decade later, around age 60, research shows.

• Normal aging. Studies show that sarcopenic atrophy can lead to up to a 50% loss in muscle mass by your 80s. This is a natural part of aging, but factors like less physical activity, neurological decline, and poor nutrition can speed up the process. Staying active and eating a balanced diet can help you maintain muscle and support healthy aging.

• Nutritional deficiencies. Not getting enough protein or calories can put you at increased risk for muscle loss. “Protein provides the amino acids your body needs to build and repair muscle,” says Dr. Davis. Without enough nutrients and energy, muscles can’t stay as strong.

• Stress. Research shows that chronic stress can contribute to muscle loss. “High levels of stress hormones like cortisol may increase inflammation and make it harder for your body to get oxygen to your muscles,” says Dr. Davis.

Symptoms of muscle atrophy 

Muscle atrophy doesn’t always look the same for everyone, but there are some common signs to watch for, such as one limb appearing smaller than the other, or everyday activities feeling more tiring than usual. Other muscle atrophy symptoms can include:

• Reduced muscle mass. One arm or leg may look smaller than the other, for example.

• Fatigue. “Everyday tasks, like going up and down stairs, or carrying groceries, may feel exhausting,” says Dr. Davis. 

• Weakness in one arm or leg.

• Trouble walking or balancing.

• Muscle cramps. “When you lose muscle mass, it can affect your circulation,” says Dr. Davis. “With less blood flowing to the area, you may be more likely to experience muscle cramps.”

Treatments for muscle atrophy

Losing muscle can be concerning, but there are many things you can do to build strength and regain muscle, especially if muscle atrophy happened because of inactivity or is related to a normal part of aging, says Dr. Davis. Sticking with a regular resistance training routine and making sure you get enough protein can help a lot. Here are some practical tips to help you rebuild muscle:

• Try physical therapy and targeted exercises. Targeted exercises can help you regain muscle mass and strength in the areas you lost it. You can do exercise therapy at home or work with a physical therapist who can guide you through movements tailored to your needs. Research has shown that physical therapy is the most effective treatment for muscle atrophy. “A physical therapist can develop an individualized program to safely rebuild your strength and mobility,” says Dr. Davis. They may also use ultrasound therapy, which uses sound waves to encourage muscle healing. You can see a physical therapist in person or use a program like Hinge Health, where you may access a PT via telehealth/video visit.

• Begin a strength training routine. All types of movement are helpful, but resistance or strength training is especially effective for rebuilding muscle. Aim to do strength training twice a week, according to the current Physical Activity Guidelines for Americans. “You can start with bodyweight exercises, then add resistance bands, and eventually progress to weights,” says Dr. Davis. Consider working with a certified personal trainer or a certified strength and conditioning specialist. 

• Get nutritional support. Eating a balanced, nutrient-rich diet — especially with enough protein — is key to rebuilding muscle. Most adults need about 0.8 grams of protein per kilogram of body weight (about 60 grams a day if you weigh 165 pounds), but adults over 40 may need more. Choose healthy protein sources like eggs, fish, lean meats, low-fat dairy, soy, and nuts, Dr. Davis recommends. Consider working with a registered dietitian. 

• Consider supplements. Creatine is a popular supplement that’s often used to support muscle growth, especially when paired with strength training. Although creatine is naturally found in animal proteins, many take it as a supplement (either in capsule or powder form) to help increase strength and muscle mass. However, research suggests there isn’t enough evidence yet to show whether creatine can help rebuild muscle in older adults with sarcopenia. Talk to your doctor before starting any new supplement.

• Try electrical stimulation. For muscle loss related to neurogenic atrophy, your physical therapist may suggest electrical stimulation. This involves placing small electrodes on your skin that send gentle impulses to help your nerves and muscles contract. While this won’t reverse muscle atrophy, it can help maintain muscle strength.

• Ask about medical interventions. If your muscle atrophy is related to a medical condition — such as low testosterone or type 2 diabetes — your doctor can help you manage these issues with drugs and other interventions, says Dr. Davis.

Can muscle atrophy be reversed?

If you have disuse or age-related (sarcopenic) atrophy, muscle loss is often reversible. “The sooner muscle loss is addressed, the better your chances are for regaining strength and function,” says Dr. Davis. By following your physical therapy plan, staying active, and eating a protein-rich diet, you may start noticing improvements within a few weeks, though progress will look different for everyone.

While muscle loss caused by nerve problems or serious illnesses can’t always be completely reversed, physical therapy can still help you maintain as much muscle as possible. This can make it easier to stay active and independent in your daily life.

When to see a doctor

Muscle atrophy is often a normal part of aging, but it’s important to check in with your doctor if you notice it progressing quickly, says Dr. Davis. Seek medical attention if you:

• Lose muscle mass for unclear reasons

• Have other unusual or worrisome symptoms, including numbness or weakness

• Experience unexplained weight loss or severe fatigue

PT tip: Keep moving

“Staying active is the most effective way to reverse and prevent muscle atrophy,” says Dr. Davis. Even if movement feels challenging, try to walk, stretch, or gently lift something daily. “The more you move, the more you support your recovery,” says Dr. Davis. “Being sedentary can make things tougher in the long run.”

How Hinge Health can help you

If you have joint or muscle pain that makes it hard to move, you can get the relief you’ve been looking for with Hinge Health’s online exercise therapy program.

The best part: You don’t have to leave your home because our program is digital. That means you can easily get the care you need through our app when and where it works for you.

Through our program, you’ll have access to therapeutic exercises and stretches for your condition. Additionally, you’ll have a personal care team to guide, support, and tailor our program to you.

See if you qualify for Hinge Health and confirm free coverage through your employer or benefit plan here.

This article and its contents are provided for educational and informational purposes only and do not constitute medical advice or professional services specific to you or your medical condition.

References 

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2. Khadilkar, S. S. (2019). Musculoskeletal Disorders and Menopause. The Journal of Obstetrics and Gynecology of India, 69(2), 99–103. doi:10.1007/s13224-019-01213-7

3. Hurst, C., Robinson, S. M., Witham, M. D., Dodds, R. M., Granic, A., Buckland, C., De Biase, S., Finnegan, S., Rochester, L., Skelton, D. A., & Sayer, A. A. (2022). Resistance exercise as a treatment for sarcopenia: prescription and delivery. Age and Ageing, 51(2). doi:10.1093/ageing/afac003

4. Wu, S.-H. (2022). Creatine supplementation for muscle growth: A scoping review of randomized clinical trials from 2012 to 2021. Nutrients, 14(6), 1255. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8949037/

5. Wolfe, R. R., Miller, S. L., & Miller, K. B. (2008). Optimal protein intake in the elderly. Clinical Nutrition, 27(5), 675–684. doi:10.1016/j.clnu.2008.06.008

6. Office of Disease Prevention and Health Promotion. (2021). Current Guidelines | odphp.health.gov. Health.gov. https://odphp.health.gov/our-work/nutrition-physical-activity/physical-activity-guidelines/current-guidelines

7. Walston, J. D. (2012). Sarcopenia in Older Adults. Current Opinion in Rheumatology, 24(6), 623–627. doi:10.1097/bor.0b013e328358d59b