Any muscle on your body can be strained. Some muscles—the hamstring, for instance—seem more susceptible to strains due largely to the injury mechanism. Essentially, muscle strains are tears in muscle fibers, ranging from micro tears to complete ruptures. Generally, muscle strains are caused by overstretching or overloading a muscle.
Imagine your muscle as a piece of paper. Gentle, consistent pulls on the sheet of paper won’t necessarily rip it. However, continue adding pressure as you pull and eventually the paper will give. Let’s extend that analogy a step further. Rather than slowly adding pressure to your pulls on the paper, snap it in a quick jerk. The chances of ripping that paper increase dramatically. Your muscle reacts in much the same way. Gentle, consistent forces may not cause tears in your muscle—in fact, your muscles are designed to deal with just such forces. But keep adding more and more weight or force to those actions and your muscle fibers will eventually tear. The second example—snapping the paper—closely simulates the explosive movements common to athletic events. Athletes often go from static to active in one quick motion, in effect “snapping” the muscle. Just like the piece of paper, your muscle’s response to such a dramatic and quick application of force is often to tear.
While athletic events are most often the culprit when it comes to muscle strains, there are any number of ways to strain a muscle. Heavy lifting; sudden, jerky movements; insufficient warm-up; activity in weak or under-conditioned muscle; fatigue; previous injury; and even direct impact can all contribute to causing a muscle strain.
Now that we know how muscle strains can happen, how do you know if you have one?
Believe me, you’ll know if have a strained muscle. But here’s some of the more common symptoms, just in case. You may experience any of the following separately, in any combination, or, in a worst-case scenario, all of them.
A “popping” sensation or even an audible pop at the moment of injury.
Redness, swelling, or bruising.
Pain when the injured muscle or associated joint is used or even at rest.
Weakness in the affected muscle or associated joint (in severe injuries, you may not be able to use the muscle or joint at all).
Before we get into how to deal with muscle strains, there’s one more thing you need to know about these pesky injuries. Muscle strains are actually graded (no, not “A”, “B”, or “C”, but grade 1, grade 2, and grade 3) according to their severity.
A grade 1 muscle strain involves tears to around 10% of the muscle fibers. This is only a mild strain, but you will still experience pain and some loss of function.
Grade 2 muscle strains happen when between 10 to 50% of the muscle fibers are torn. While the muscle is not completely ruptured, grade 2 muscle strains are still serious and will take time to heal.
If you ever have a grade 3 muscle strain, you can count on extensive rehabilitation. A grade 3 muscle strain means that more than 50%—or even the entire muscle—has been damaged. Grade 3 muscle strains often require corrective surgery and long hours in physical therapy.