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Pulling a Muscle: Flex Your Smarts First

The human body is able to pull, push, and pump because of healthy muscles. Keep muscle strain from knocking it out of commission with Groupon’s explanation of how pulled muscles happen.

Ten out of ten gym teachers agree: warm up before you work out. The consequence of ignoring their advice may be a pulled muscle (also called a distraction rupture or strain), which happens when muscle fibers are stretched beyond their limit.

Doctors divide muscle strains into three categories. A first-degree strain is generally what athletes talk about when they say they’ve pulled a muscle—a very slight tear damaging less than 5% of the muscle, causing discomfort and swelling but little loss of function. A second-degree strain produces a much more noticeable tear and pain when trying to contract the muscle, and a third-degree strain, or rupture, is a complete tear across the muscle’s width that takes the muscle completely out of commission and may even require surgery. Many people confuse strains with sprains, though a sprain can only refer to damage done to ligaments, not muscle.

Muscles most often get pulled because they’re stretched too quickly, whether by a burst of speed on the track or a too-sudden lift of the family mastiff. Warming up creates more flexibility by literally raising the tissue’s temperature, optimally by one to three degrees. That’s why trainers prefer to use dynamic, cardio-based moves during the warm-up period: trying to create flexibility by forcing cool muscles into a static stretch might itself be a recipe for a pull.