Muscle Strains: Why do they Happen?

To prevent muscle strains, we must train correctly and intensely. It's also important to get a good warm up, among other measures that we'll discuss below.
Muscle Strains: Why do they Happen?

Last update: 01 June, 2020

Muscle strains are one of the most frequent injuries for any type of athlete. After all, the only things we actively move in the body are the muscles.

The specific movements that our muscles perform are contracting and relaxing, which allows them to stretch. Therefore, any sport that we practice involves a combination of muscle contractions and relaxations.

Active causes for muscle strains

So, if this movement is so normal and frequent, why do muscle strains occur so often? Let’s analyze the most obvious cases.

Excessive effort

One cause for muscle strains is simply trying to make an effort that the body isn’t prepared to withstand. As we train the muscles, they become stronger and more resilient. But if a certain muscle isn’t prepared, and we demand excessive or sudden force, it can tear.

We can also understand this if we consider that DOMS are small muscle strains. For example, if we’re not used to doing a lot of physical activity, and we decide to move some heavy furniture around, this can lead to muscle soreness. We can also experience muscle aches if we go to play a soccer game with friends after many years of being inactive.

But it’s also possible to subject a muscle to a violent contraction that tears it even if we’re physically prepared. The more intense our workouts are, the more prepared we’ll be to withstand the efforts, although it depends on how strenuous they are.

A girl feeling pain in her leg after running due to muscle strains

It’s also worth talking about muscles that have suffered a recent injury. For these muscles, which spend weeks or even months without contracting properly, practically any type of contraction will be a great effort. Therefore, we must ensure that our injured muscles recover gradually.

Prolonged work

Another way to get muscle strains is to play sports for such a long period of time that the muscle can’t take it and ends up tearing. As with sudden efforts, it’s important to train enough, and gradually increase the intensity of the sessions, in order to face the final challenge that we’ve set for ourselves.

Poor muscle balance

Within the muscle groups, there are agonists (those which perform a certain movement) and antagonists (those which perform the opposite movement). When playing a sport, both muscle groups keep the other “inline”.

If an agonist is much stronger than an antagonist and the first one is contracting violently, the antagonist may not be able to control the movement and end up overstretching. This would probably cause the antagonist muscle to tear.

Insufficient warm-up

This case speaks for itself. As the name suggests, warming up consists of preparing or conditioning the muscles for the effort that we’re going to subject them to. If we don’t warm up long enough or with the right intensity, our muscles won’t be prepared, and there will be a higher risk of them tearing.

Extrinsic causes of muscle strains

Lack of rest

It’s important to dedicate enough time to rest. When we do a sport, we have to give the body time to recover. If we sleep poorly, fewer hours than necessary, or we try to practice intense sports without breaks in between, we also increase the possibility of tearing a muscle.

A woman feeling tired after a intense workout with a proper warm up to avoid muscle strains

Inadequate sports equipment

Using inappropriate sports equipment can cause various injuries. Inappropriate can mean that the equipment is poor quality, worn, or directly unsuitable for body ergonomics. In all these cases, using it will force the muscles to work unnaturally, which can lead to muscle strains, among other problems.

Malnutrition

If we don’t eat food in adequate amounts, the muscle fibers won’t have access to the nutrients they need. This will make them weaker and therefore, less resistant to repeated contractions.

Other possible causes for muscle strains

People with poor blood circulation, as well as those with diseases such as diabetes, should be especially careful. In these cases, the muscle can’t use the resources that are available because not enough blood gets to them.

The weather may also have some influence in this regard. Training in a cold, wet environment makes it harder to warm up your muscles; it also reduces their flexibility. Therefore, we must be careful when training with this type of weather.

Prevention of muscle strains

With all the information above in mind, the most effective way to prevent muscle strains is to have trained muscles and not subject them to efforts that they’re not prepared for. Remember: train thoughtfully and intensely, eat well, get enough sleep, and use the proper sports equipment.


All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.


  • F. Ruiz. Estudio nutricional en futbolistas. Tesis doctoral en la Universidad del País Vasco, 2006.
  • J-L. Croisier, J-M. Crielaard. Hamstring muscle tear with recurrent complaints: An isokinetic profile. Isokinetics and Exercise Science, vol. 8, no. 3, pp. 175-180, 2000
  • M. Friedman, J. Stensby, T. Hillen, et al. Traumatic Tear of the Latissimus Dorsi Myotendinous Junction: Case Report of a CrossFit-Related Injury. Sports Health. Vol 7, Issue 6, 2015

This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.