Strain vs. Sprain: What's the Difference?

Sprains and strains are common injuries among avid movers. They share similar signs and symptoms, but the difference comes down to ligaments vs. tendons.

Brock Armstrong
7-minute read
Episode #398

Let me set the stage: it’s a sunny Summer day and you decide to go for an early morning jog. You down your coffee, slip on your running shoes, and head out the door. A few minutes later you are cruising along the trail, lost in your thoughts when an enthusiastic dog darts out toward you. You suddenly snap out of your daydream and dodge the happily bounding dog, but while doing so, you plant your foot in a less than optimum way and feel a pain that reminds you of that time you sprained (or strained?) your wrist playing hockey.

Later that day you stop in at the walk-in clinic to have a medical professional look at your slightly swollen and achy ankle. The doc says not to worry about it, it is just a strain (or was it a sprain?). Take it easy and you should be good to go after a few days rest and RICE. Phew!

The Difference Between a Strain and a Sprain

Sprains and strains both refer to damage to the soft tissues in the body, including ligaments, tendons, and muscles. They are both common injuries, for those of us who use our bodies in new and exciting ways each day, and they both share some common symptoms. What it comes down to is which soft tissue—ligament or tendon—has been affected.

The difference is which soft tissue—ligament or tendon—has been affected.

A ligament is a tough band of fibrous tissue that connects bones to other bones or cartilage and is usually located around joints. A tendon is a tough cord of fibrous tissue that connects muscles to bones. And that, right there, is the main differentiating factor.

  • A sprain is an overstretched, torn, or twisted ligament. Commonly sprained areas include the wrists, ankles, thumbs, and knees.
  • A strain is an overstretched, torn, or twisted tendon or muscle. Commonly strained areas include the legs, knees, feet, and back.

Is this an important distinction to make? Well, honestly, not really. At least not for us laymen. But it does matter to the medical professional who is giving advice on how to treat, manage, or heal that tender ankle.

How Muscles and Tendons Get Strained

In an oversimplified nutshell, the muscles you have doing all that work underneath your skin are made up of a large number of smaller bundles of muscle fibers called fascicles. These fascicles are made up of individual muscle fibers that are all crosslinked so they can slide back and forth inside the fascicle.

Gradually, near the ends of the muscle, these muscle fibers turn into tendon fibers and then attach to the bone. Each tendon is different, depending greatly on its location in the body, and a tendon can range from being pretty short to pretty darn long.

Strain Causes

A strain occurs when damage is caused by an overstretched muscle or tendon, pulling their fibers apart, and therefore losing the ability to adequately contract. The severity of strain depends on whether the muscle fiber is just over-stretched, partially torn, or completely torn. The strain (or damage) can occur in three areas: the muscle itself, the intersection where muscle fibers turn into tendon fibers, or right in the tendon itself.

A strain can occur from one single wipeout or incident, or it can gradually build up over time and repeated use. The most common strain is from overuse (repetitive use injury) but muscles and joints can also be acutely forced to do things that they are not prepared or designed to do and that can also result in a strain.

Strains happen while playing sports or other activities that involve repetitive movements, sitting or standing in an awkward position for a prolonged time, lifting a heavy object, or simply slipping and falling.

A strain can occur from one single wipeout or incident, or it can gradually build up over time and repeated use.

Strain Grades

  • Grade 1: stretching of a few of the muscle fibers.
  • Grade 2: muscle fibers are damaged or torn.
  • Grade 3: complete rupture of the muscle. Ouch!

Strain Symptoms

  • Swelling
  • Bruising
  • Limited mobility
  • Pain or tenderness
  • Muscle spasms or cramping
  • Muscle weakness


All content here is for informational purposes only. This content does not replace the professional judgment of your own health provider. Please consult a licensed health professional for all individual questions and issues.

About the Author

Brock Armstrong Get-Fit Guy

Brock Armstrong was the host of the Get-Fit Guy podcast between 2017 and 2021. He is a certified AFLCA Group Fitness Leader with a designation in Portable Equipment, NCCP and CAC Triathlon Coach, and a TnT certified run coach. He is also on the board of advisors for the Primal Health Coach Institute and a guest faculty member of the Human Potential Institute.