Whether you're shoveling snow, walking to work, or playing a game of pick-up basketball, it's bound to happen sooner or later: pain. Maybe you say you "strained a muscle," "sprained your ankle," or even "tore" something. But what's really going on here?

You Might Also Like
{{displayTitle}} READ

"Sprain and strain are medical terms, but both of them can mean tear," says David Neuman, M.D., an orthopedic surgeon at NY SportsCare.

In short, strains involve tearing or over-stretching a muscle or tendon, while sprains are the tearing of a ligament (more details on that soon). Strains and sprains come in three different severities: grade I, grade II, and grade III. The higher the grade, the more painful and severe the injury.

A grade I strain or sprain can be a very slight tear or over-stretching a muscle and may have little inflammation, Neuman says. Grade II is slightly more severe, and grade III is a complete rupture of the tendon or the ligament.

With a grade III, you're going to experience a high level of pain, says Colleen Brough, a physical therapist and assistant professor at Columbia University in New York City. "It doesn't get better, and a person really can't tolerate weight bearing or walking on it." Chances are, if you have a grade III injury, you'll know it.

But what about all those other times when you've just got a little pain and you're not exactly sure what to do next? We've rounded up answers to your most common sprain and strain issues.

Is It a Sprain, Strain, or Something Else?

What's Actually Happening Inside

What's the Difference Between a Sprain and Strain?

Like we mentioned above, a strain occurs when a muscle or tendon tears. "If it's the first time it's happening, a muscle strain is usually soreness in the belly [middle] of the muscle," Brough says. A strain can also occur at one end of the muscle—that's where the tendon tearing comes in. "That's a more difficult strain to fix," Brough says. There's a common theme to a lot of the advice in this article: When you notice pain—stop and rest. Don't "push through;" it'll do no good in the long run.

Sprains most commonly occur in the ankle and refer to a ligament tear. "Ligaments hold bones together," Neuman says. "Think of it as a small rope that runs from one bone to another." Following that rope analogy, you can use the grading system: a grade I is when the rope frays slightly; grade II, the rope is hanging on by a few threads; grade III, the rope is severed completely.

Depending on the severity, you may not be able to put any weight on the injured area. Neuman says you'll also usually notice the "cardinal signs of inflammation": redness, warmth, stiffness, and pain.

How It Happens

Bummer alert: Strains and sprains can happen in a number of ways. If you're a regular runner but increase your mileage or try a new sport, like tennis, which involves a lot of darting back-and-forth, you're at risk for an injury, Brough says.

In some cases, you'll know how it happened right away. Maybe you tripped and heard a loud "pop" or twisted your ankle and immediately couldn't put pressure on it.

In the case of a strain, maybe you tried a new sport and after one quick move, you felt a small tweak of sharp pain in the middle of a muscle. Other times, the onset can be more subtle, but it still usually appears within one day after the activity, Brough says. Translation: If you're sore a day or two after a tough workout, it's probably not a strain or sprain. (It's more likely delayed onset muscle soreness, DOMS.)

How to Heal

What's the Difference Between a Sprain and Strain?

If the pain isn't excruciating, you can take R.I.C.E. measures at home: rest, ice the area, compress the injury, and elevate it. Neuman also says you need to be "pre-active before you're active. Let your body heal the torn tissue before you start using it again."

Brough suggests staying off the area for three days. "You're going to feel better, but it takes four full weeks—a whole month—for that tissue to really heal," Brough says.

Her advice? If you feel better after at least three rest days, try a short warm-up workout. Maybe a short walk (no more than one mile), for instance. The risk is that you'll disrupt the healing process and soon be faced with a chronic injury—which is much harder to heal. If you feel pain again during your light workout, it may be time to see a doctor, Brough says. Likewise if you're not improving or the injury gets worse after three to five days of rest, it's time to see a doctor.

Once you see a doctor, the treatment will vary depending on your exact injury. But in general, "if the injury isn't super serious, you'll probably be sent to physical therapy," Brough says.

How to Prevent It

If you're new to a program or you're recovering from an injury, start slowly and take rest days between training sessions. "You have to let your body recover so it's ready for that workout again," Neuman says. When you don't let your body fully recover, that's when you start to run the risk over overuse-type injuries, Neuman says.

In general, take time to warm up properly, ease into new workouts, and know your limits.

READ THIS NEXT: Why Do Some Runs Feel So Freaking Hard? Overshare Promo