Stiff and sore muscles can be a typical part of exercising. This can mean the muscles are working well and getting stronger. But, it may also be caused by other conditions requiring medical treatment.

Muscle stiffness can feel like an ache or discomfort in the muscles. It may also resemble a feeling of the muscles “tightening” up.

Read on to learn what causes muscle stiffness and how to relieve or treat it.

There are numerous potential causes for muscle stiffness. Some, such as pain from exercise and sports-related injuries, can be common.

Exercise

One of the most common causes of muscle stiffness is exercise.

Exercise is an essential element to a healthy lifestyle. It enables the bones and muscles to grow stronger and helps with heart and lung function.

But exercise can sometimes cause muscles to be sore.

This is particularly common when trying new forms of exercise. When this happens, you may use a new muscle you aren’t used to using. This can cause small tears in the fiber of the muscle or even strain the muscle.

This can happen during exercise or in the hours following and can feel like stiff, tight, or aching muscles.

As this happens, the muscles are working to repair themselves and also become stronger.

In some cases, pain in the muscles won’t begin until 12 to 24 hours following exercise. This is known as delayed onset muscle soreness (DOMS). In DOMS, pain may be at its worst 24 to 72 hours following exercise.

Injuries

Injuries to soft tissue are most common in the muscles, tendons, and ligaments. This can occur during sport, exercise, or everyday activities.

Two forms of soft tissue injuries include:

  • acute injuries, which can be caused by a twist, fall, or sudden blow to the body. Sprains and strains are examples of acute injuries.
  • overuse injuries, which can happen when an activity is repeated so regularly the muscles don’t have enough time to heal between repetitions. Tendinitis and bursitis are examples of overuse injuries.

The severity of injuries can vary, as well as the symptoms that accompany them. In addition to a feeling of tightness or stiffness, other possible symptoms include:

  • cramping
  • aches
  • spasms
  • pain
  • swelling
  • weakness

While muscle stiffness may occur because of exercise or injury, it can also be the result of other factors such as an underlying condition or a side effect of some medications.

Lupus

Lupus is an autoimmune disease that can impact almost any organ in the body. The disease can cause periods of flare-ups, when symptoms worsen, and periods of remission, when symptoms can improve.

Symptoms of lupus can vary between people. Along with muscle stiffness, other possible symptoms of lupus include:

  • pain in the joints or muscles
  • chest pain
  • rash
  • fever
  • sensitivity to light
  • hair loss
  • anemia
  • prolonged fatigue
  • mouth sores
  • kidney problems
  • memory issues

Lyme disease

Lyme disease is transmitted to humans through tick bites. It’s the most common vector-borne disease in the United States.

If left untreated, Lyme disease can cause a variety of symptoms, including muscle aches and pains as well as neck stiffness.

Other symptoms may include:

  • headache
  • fatigue
  • chills
  • fever
  • swollen lymph nodes
  • rash
  • pain and swelling in joints
  • irregular heartbeat or palpitations
  • episodes of shortness of breaths
  • episodes of dizziness
  • tingling, pain, or numbness in the hands or feet

Infectious mononucleosis

Infectious mononucleosis is an infectious disease that’s common among teenagers, young adults, and college students.

Symptoms may occur slowly over time and may not all be present at the same time. Along with muscle stiffness and muscle aches, other possible symptoms include:

  • rash
  • sore throat
  • headache
  • extreme fatigue
  • swollen spleen
  • swollen liver
  • swollen lymph nodes in the armpits and neck
  • fever

Symptoms may improve for some people in 2 to 4 weeks, but others may experience symptoms several weeks or even months later.

Fibromyalgia

Fibromyalgia can cause widespread pain all over the body.

Along with stiffness and pain that can happen all over the body, other symptoms of fibromyalgia include:

  • fatigue
  • sleep difficulties
  • headache or migraine
  • anxiety
  • depression
  • cognition difficulties
  • tingling or numb hands and feet
  • pain in the jaw or face
  • digestive issues

ADHD medications

Some medications used in the treatment of attention deficit hyperactivity disorder (ADHD) can cause muscle stiffness. In some people, medications, such as dexmethylphenidate, can cause severe muscle stiffness and pain.

Polymyalgia rheumatica

Polymyalgia rheumatica (PMR) is a common cause of stiffness and aching across the body that occurs in people older than 50.

Stiffness and aching because of PMR are most common in the:

  • upper arms
  • lower back
  • thighs
  • neck

Stiffness and pain may be worse in the morning.

Any time you have pain that concerns you, you should consider seeing a doctor or healthcare professional.

If you have muscle stiffness along with other symptoms such as fever, fatigue, sore throat, or headache, you should consider making an appointment to see a doctor.

Muscle stiffness can sometimes be because of exercise or injury, and this can often be managed at home without seeing a doctor. But there are times when you should see a doctor if stiffness or pain doesn’t improve, including:

  • Your stiffness or pain lasts for longer than a week.
  • The pain prevents you from moving.
  • The pain is unbearable.
  • The pain worsens when you exercise.
  • The pain is causing trouble breathing or dizziness.
  • Your muscles are red, swollen, or warm.
  • You’re experiencing pain in the joints, in the tendons, or over the bones.

To diagnose the cause of muscle stiffness, a doctor will take a full medical history and ask questions about any potential injuries or exercises that may have contributed to muscle stiffness.

They may perform a physical exam of the stiff muscles and order tests such as an MRI scan or X-ray.

Treating muscle stiffness will depend on the cause. A doctor will be able to advise the best way to treat muscle stiffness.

Home treatments

In some cases, such as muscle stiffness caused by exercise or injury, at-home treatments may be all that’s required.

These may include:

  • massage
  • heat through a warm bath or shower
  • ice to lower inflammation
  • over-the-counter (OTC) medications (such as ibuprofen)
  • OTC creams and gels (such as Icy Hot or Aspercreme)
  • rest

It’s not always possible to prevent muscle stiffness, particularly if it’s because of an underlying condition. But there are some steps you can take to try to prevent stiff and sore muscles.

These include:

  • drinking water
  • warming up properly before exercise
  • using proper technique when exercising
  • cooling down and stretching after exercise
  • not pushing yourself too hard when exercising

Stretches

Stretching is important for keeping muscles flexible and preventing stiffness. It can decrease muscle stiffness, improve circulation, and reduce inflammation.

Instructions on how to stretch specific muscle groups include the following:

Thighs: Do quad stretches by standing up straight, bending one leg at the knee, and raising your foot toward your back. You can hold your foot or ankle with your hand for 10 to 15 seconds and then switch sides.

Neck: Stand upright or sit on a chair or on the floor. Try to relax your body as much as possible. Slowly roll your neck from one side down your chest to the other side. Repeat for several circulations.

Lower back: Lie flat on your back, bend your left knee, and pull it into your body. Your shoulders and back should stay flat on the ground. Hold for about 10 to 20 seconds and switch sides.

Muscle stiffness can have numerous causes. The most common cause is muscle stiffness due to exercise or injury. Muscle stiffness can also be caused by underlying conditions such as lupus, Lyme disease, or fibromyalgia. In some cases, muscle stiffness can be treated with at home remedies, but some underlying conditions will require treatment with a doctor.