What Are Muscle Strains?
Doctors define a strain as an injury to a muscle or tendon. The term strain can include anything from an overstretched tendon or muscle fiber to a complete tear or rupture.
Athletes who participate in contact sports, like football, basketball, and wrestling, are at risk for strains. But so are gymnasts, tennis players, golfers, and any athlete who uses the same muscles over and over.
In fact, muscle strain is among the most common athletic injuries.
Strains occur when your muscle stretches beyond its normal range of motion. It can also occur when you put more load on the muscle than it's strong enough to handle.
When this happens, the muscle fibers tear, resulting in a pulled muscle. Doctors grade strains — from first degree to third degree — based on how much muscle fiber you've torn.
A muscle strain isn't the same as a muscle sprain. A sprain is an injury to a ligament (the bands that provide stability between your joints). Sprains tend to happen in the ankles, knees, and wrists, whereas strains can happen to any muscle.
What Are the Types of Muscle Strains?
In sports, it's possible to pull almost any muscle. The most common sports strains affect the leg or groin muscles, such as the:
- Quadriceps — the muscle in the front of your thigh.
- Hamstring — the muscle in the back of your thigh.
There are three types of muscle strains:
- Mild muscle strain, or grade 1. With this type of strain, you have slight damage to your muscle fibers. You usually have only a minimal loss of strength or range of motion.
- Moderate muscle strain, or grade 2. This type of strain affects more muscle fibers than a mild one. It's likely more painful, with a more significant loss of range of motion.
- Severe muscle strain, or grade 3. A severe strain can mean a complete rupture of a muscle or tendon. If it's severe enough, it can require surgery.
What Causes Muscle Strains?
Common causes of muscle strains include:
- Playing sports.
- Pushing or pulling something heavy.
- Exercising.
- Falling.
While many different motions can cause you to pull a muscle, there are some specific reasons athletes wind up with strains. These include:
- Having generally tight muscles — especially combined with a lack of strength in the muscle. In other words, you've pushed a muscle lacking in flexibility and strength too far.
- Overusing the same muscle or muscle groups. Bending, leaping, gripping, or twisting in the same way, over and over, can strain a muscle or tendon.
- Not warming up or doing too much too fast. You are more likely to injure cold muscles because they are tighter. But loading a muscle too fast can also lead to injury.
What Are the Risk Factors and Complications of Muscle Strains?
The motions involved in high-impact sports can put you at risk of strained muscles.
For example, a:
- Groin strain can come from quick, side-to-side motions.
- Thigh muscle strain often happens when you suddenly speed up or slow down while running.
Age is also a risk factor since our muscles lose strength and flexibility as we age. Having a previous muscle or tendon injury also makes you more likely to have a re-injury.
Sports specialization can be a risk factor for young athletes. Playing one sport all year round can lead to muscle overuse.
How Do You Prevent Muscle Strains?
Warming up before physical activity is key to helping prevent muscle strains and other muscle injuries. For example, gentle stretching and light calisthenics can help warm up muscles before a workout. Warm-up activities include jumping jacks, burpees, or jogging in place.
It's also helpful to work on muscle flexibility and strength. Core strength classes, like yoga and Pilates, can help lengthen and strengthen muscles. Weight training (with proper technique) can also help target weak muscles prone to injury.
If you've had a previous muscle injury, ensure you are completely healed before returning to full activity. Physical therapy can be helpful for this. Physical therapists can also suggest activity modifications that don't overtax previously-strained muscles.