Stretching before and after working out has long been a given.

But researchers now say stretching may not only prevent you from reaching your maximum strength during a workout, but it also could leave you more vulnerable to injury.

There are generally two stretching techniques: dynamic stretching and static stretching. Dynamic stretching is ideally done before a workout and it involves a concise range of motion meant to mimic the movement we make during rigorous exercise. Static stretching involves extending your arms, legs or other body parts to the point of tension and holding that position for a period of time.

Health and medical professionals in the past have encouraged stretching before physical activity as a means of improving flexibility, the full range of motion we can move our joints and muscles in. Flexibility in joints and muscles has proven to be essential in warding off injuries and soreness.

A research team form the University of Zagreb analyzed 104 studies from past years where participants were asked to stretch prior to engaging in physical activity. Researchers used studies that focused on static stretching and stayed away from ones that included a separate activity between stretching and working out.

After evaluating all the data they found that the strength in muscles that were stretched prior to working out decreased by five and half percent. The decrease in strength worsened if the static stretch was held for over 90 second, NYTimes reported.

The study also found that explosive muscular performance -- such as jumping as high as you can or running as hard as you can -- decreased by almost three percent if stretching was done pre-workout.

While experts have not yet honed in on what it is about stretching that inhibits proper muscle function, the research team does believe that the actual stretching of tendons in the muscle may cause the weakening of the muscle itself.

For your best bet, experts urge gym rats to stretch only those muscles they plan to utilize during their workout and to limit the amount of time each stretch takes.