5 Common Reasons for Low Back Pain—and What to Do Next
By Michael Ricchiuto, MPT, MBA
Founder and Physical Therapist, Physical Therapy Now
Updated August 6, 2026
Low back pain can make almost every part of the day more difficult.
It may hurt when you first get out of bed, sit at work, stand from a chair, lift groceries, exercise, or try to sleep. Sometimes the pain begins after an obvious injury. In other cases, it gradually appears without one clear event.
The location of the pain does not always identify its source. Muscles, spinal joints, discs, nerves, hips, and movement patterns can all contribute to pain in the lower back.
The five causes below are among the most common problems associated with low back pain. However, the only reliable way to determine what may be contributing to your symptoms is through an individualized evaluation.
At a Glance: What Commonly Causes Low Back Pain?
Five common reasons for low back pain include:
- Muscle or ligament strains
- Irritated or herniated spinal discs
- Arthritis and irritation of the spinal joints
- Spinal stenosis or nerve compression
- Weakness, stiffness, and repeated movement stress
Each problem can feel different, and several factors may be present at the same time.
1. A Muscle or Ligament Strain
A strain or sprain is one of the most common causes of low back pain.
The muscles and ligaments surrounding the spine help control movement, maintain stability, and manage the forces placed on your body. These tissues may become irritated when they are exposed to more stress than they are prepared to tolerate.
A strain can occur after:
- Lifting or carrying something heavy
- Twisting while lifting
- Shoveling snow or doing yardwork
- Beginning a new exercise program too quickly
- Repeating the same work activity
- Making a sudden or awkward movement
- Returning to sports after a period of inactivity
Pain from a strain may feel sore, tight, sharp, or spasmodic. It may remain in the lower back or spread into the buttock without traveling farther down the leg.
Muscle strains do not always require a dramatic injury. A sudden increase in activity can irritate the back even when each individual movement seems harmless. Strains and sprains are recognized as a frequent source of back pain.
What may help?
Complete bed rest is generally not the answer. Light activity and walking may be appropriate as long as they do not substantially increase your symptoms.
A physical therapist can evaluate which movements are painful, determine whether mobility or strength limitations are contributing, and develop a gradual plan for returning to normal activity.
2. An Irritated, Bulging, or Herniated Disc
The discs between the bones of your spine help absorb force and allow your back to move.
A disc may become irritated or change shape over time. In some cases, disc material can place pressure on or chemically irritate a nearby nerve. This is commonly described as a bulging or herniated disc.
A disc problem may cause:
- Central low back pain
- Pain that travels into the buttock or leg
- Tingling or numbness
- Pain with prolonged sitting
- Pain when bending forward
- Pain with coughing or sneezing
- Weakness in part of the leg or foot
Pain that travels along a spinal nerve is often called radicular pain. “Sciatica” is a commonly used term for symptoms that travel along the sciatic nerve into the buttock or leg.
An MRI showing a disc bulge does not automatically mean the disc is the cause of your symptoms. Imaging findings must be considered alongside your symptoms, medical history, strength, sensation, reflexes, movement, and functional limitations.
What may help?
Treatment should be based on how your symptoms respond—not simply on the wording of an imaging report.
Physical therapy may include movement strategies, progressive exercise, trunk and hip strengthening, manual treatment, education, and modification of activities that repeatedly aggravate the nerve.
You should seek prompt medical evaluation when leg symptoms are worsening, weakness is progressing, or bowel or bladder control changes occur.
3. Arthritis and Irritation of the Spinal Joints
The spine contains small joints known as facet joints. Like the knee, hip, or shoulder, these joints can become stiff or irritated.
Age-related changes may include:
- Osteoarthritis
- Changes in cartilage
- Bone-spur formation
- Disc-height changes
- Reduced joint mobility
- Increased stiffness in the surrounding tissues
These changes are common as people get older, but they do not always cause pain. The presence of arthritis on an X-ray does not determine how active or comfortable a person can become.
Symptoms associated with joint irritation may include:
- Aching across one side of the lower back
- Stiffness after inactivity
- Pain when standing or walking
- Pain when leaning backward or rotating
- Difficulty getting upright after sitting
- Reduced tolerance for prolonged positions
Arthritis and other age-related spinal changes are recognized causes of back pain, but symptoms and function vary significantly from one person to another.
What may help?
The objective is not to reverse every structural change. The goal is to improve how well your body moves and manages daily activity.
Treatment may focus on:
- Improving hip and spinal mobility
- Strengthening the trunk and legs
- Increasing walking tolerance
- Modifying painful positions
- Improving lifting and movement strategies
- Gradually rebuilding activity tolerance
Many people with spinal arthritis can remain active when their treatment is matched to their specific limitations and goals.
4. Spinal Stenosis or Nerve Compression
Spinal stenosis refers to narrowing around the spinal canal or the spaces through which spinal nerves travel.
It is more common in older adults and may occur alongside arthritis, disc changes, or bone-spur formation.
Common symptoms can include:
- Low back discomfort
- Pain, heaviness, numbness, or weakness in the legs
- Symptoms that become worse while standing or walking
- Relief when sitting or leaning forward
- Difficulty walking through a store without leaning on a cart
- Reduced standing and walking endurance
Not everyone with spinal narrowing on an MRI develops symptoms. A physical examination helps determine whether the imaging findings are consistent with the person’s actual problem.
Spinal stenosis and narrowing around the nerves are established structural causes of low back and leg symptoms.
What may help?
Physical therapy cannot enlarge the spinal canal, but it may improve mobility, strength, balance, walking capacity, and a person’s ability to manage daily activities.
Treatment may include:
- Positions that temporarily reduce symptoms
- Hip and trunk strengthening
- Flexibility and mobility exercises
- Balance training
- Walking or cycling programs
- Gradual endurance training
- Strategies for completing daily activities with fewer symptoms
Progressive weakness, significant loss of balance, or rapidly worsening symptoms should receive medical attention.
5. Weakness, Stiffness, and Repeated Movement Stress
Many episodes of low back pain do not come from one clearly damaged structure.
Pain may develop when the body repeatedly performs an activity without enough strength, mobility, recovery, or variation. The problem may involve the back, but limitations in the hips, legs, trunk, or upper back can change how stress is distributed.
Potential contributing factors include:
- A sudden increase in exercise
- Long periods of sitting or standing
- Reduced hip mobility
- Weakness in the trunk or legs
- Repetitive lifting
- Limited recovery between work shifts
- Returning to activity after an illness or injury
- Fear of moving after a previous painful episode
- Using the same position throughout the day
There is no single “perfect” posture that prevents all back pain. However, remaining in one position for too long or repeatedly moving in a way that aggravates your symptoms can become a problem.
What may help?
The answer is rarely a generic list of back exercises.
A physical therapy evaluation can identify:
- Which movements reproduce your symptoms
- Which movements reduce them
- Areas of weakness or stiffness
- Changes in walking or lifting mechanics
- Activities you have begun avoiding
- The physical demands of your job, sport, or daily routine
Your treatment plan should then prepare you for the activities you actually need to perform.
When Should Low Back Pain Be Evaluated?
Consider scheduling an evaluation when:
- Pain is not improving as expected
- Pain repeatedly returns
- You have stopped exercising or doing normal activities
- Sitting, standing, walking, or sleeping has become difficult
- You are changing how you move
- Symptoms travel into the buttock or leg
- You feel weaker or less stable
- You are concerned about safely returning to work or sports
Early evaluation does not mean that your condition is serious. It provides an opportunity to identify the problem, understand which activities are safe, and develop an appropriate recovery plan.
When Is Low Back Pain an Emergency?
Routine physical therapy is not the correct first step for every symptom.
Seek immediate medical care when back pain:
- Begins after a significant accident, fall, or other trauma
- Occurs with new loss of bowel or bladder control
- Occurs with fever
- Causes rapidly progressing leg weakness
- Is accompanied by numbness around the groin or saddle area
You should also contact a medical professional when pain is constant and severe at night, is accompanied by unexplained weight loss, or produces persistent weakness, numbness, or tingling in the legs.
How Physical Therapy Can Help Low Back Pain
Physical therapy should involve more than receiving a standard exercise sheet.
Your first visit may include an assessment of:
- Your symptoms and medical history
- Spinal and hip movement
- Strength
- Sensation and reflexes when appropriate
- Walking and balance
- Lifting or work-related activities
- Positions that improve or worsen your symptoms
- The activities you want to resume
Treatment may involve targeted exercise, hands-on treatment, movement retraining, education, activity modification, and a home program.
Physical therapists can help people improve strength, flexibility, posture, and movement strategies while remaining appropriately active during recovery.
Do You Need a Referral for Physical Therapy in Pennsylvania?
You may be able to begin physical therapy without first obtaining a physician’s referral through Pennsylvania’s direct-access process. This often resolves low back pain and prevents future low back pain episodes.
Schedule Low Back Pain Physical Therapy in Pittsburgh or Fox Chapel
At Physical Therapy Now, we evaluate the complete problem—not just the location where you feel pain.
Our goal is to help you understand what may be contributing to your symptoms and develop a practical plan for returning to work, exercise, sports, and everyday activities.
Fox Chapel/Glenshaw Physical Therapy Clinic
Physical Therapy Now
Hartwood Towne Centre
3392 Saxonburg Boulevard, Suite 330
Glenshaw, PA 15116
Pittsburgh—Strip District Physical Therapy Clinic
Physical Therapy Now
3117 Penn Avenue
Pittsburgh, PA 15201
Call for either location: (412) 406-8196
Schedule a Physical Therapy Evaluation
You do not need to know exactly why your back hurts before contacting us. Determining what is contributing to the problem is part of your physical therapy evaluation. The addresses and appointment telephone number above match the clinic information currently published on the Physical Therapy Now website.
Frequently Asked Questions About Low Back Pain
Is walking good for low back pain?
Walking is often a reasonable form of light activity, but it should be adjusted to your symptoms. Begin with a manageable distance and stop or modify the activity if pain or leg symptoms increase substantially.
Should I rest when my lower back hurts?
A brief reduction in aggravating activities may help, but prolonged bed rest is generally not recommended. Remaining appropriately active can help prevent additional stiffness and weakness.
Do I need an MRI before physical therapy?
Many people can begin with a physical examination rather than immediate imaging. Imaging may be appropriate after significant trauma, when serious medical concerns are present, when neurological symptoms are progressing, or when recovery does not follow the expected pattern.
Can physical therapy help a herniated disc?
Physical therapy may help manage symptoms associated with a herniated disc by improving movement, strength, activity tolerance, and nerve mobility when appropriate. Treatment depends on the person’s symptoms and examination findings.
How soon should I schedule an evaluation?
Consider an evaluation when symptoms are interfering with work, sleep, walking, exercise, or daily activity; are traveling into your leg; or are not improving as expected.
This article is intended for general educational purposes and does not replace an individualized medical evaluation, diagnosis, or emergency care.
