Static stretching is the more well-known type of stretching where there is no movement involved and often held for 20-30 seconds to promote muscle relaxation. Old-school of thought recommended a static stretching routine for 15ish minutes prior to physical activity in order to reduce the risk of injury. This pre-training ritual has lost popularity as of late because it opposes physiological responses of muscle. An elongated (relaxed) muscle is not prepared for the demands of vigorous activity, which potentially increases the risk for injury and hurts performance. For that reason, the benefits of static stretching before exercise is a myth and should be avoided at all costs!
In light of recent research studies, a paradigm shift from static stretching to dynamic stretching began. A number of studies discovered an increase in performance with dynamic warm ups. Dynamic stretching is now the preferred method for warming up because it increases heart rate, facilitates movement, activates the nervous system, stimulates blood flow, etc. These responses are more appropriate pre-exercise because it mimics sport-specific movements. This does not mean that static stretching has been phased out completely. Static stretching has been shown to be very effective to maintain functional muscle length post-exercise!